Separatist militants blew up a railway track and opened fire on a passenger train in southwestern Pakistan on Tuesday, taking dozens of hostages and battling security forces conducting a rescue operation, police and the insurgents said.

Police have not specified how many passengers were taken hostage in the remote mountainous area but the insurgents said they were holding 214 people, and have threatened to start executing them, Reuters reported.

“The affected train is still on the spot and the armed men are holding passengers,” senior district police officer Rana Dilawar said.

“Security forces launched a massive operation,” he said, adding that helicopters and special forces had been deployed.

The train was trapped in a tunnel and the driver was killed after sustaining serious injuries, local authorities, police and railway officials said.

The Baloch Liberation Army, a separatist militant group, said it blew up the tracks and “swiftly took control of the train”. The group said it would execute 10 people in response to the ongoing military operation.

The BLA has demanded the release within 48 hours of Baloch political prisoners, activists and missing persons it said had been abducted by the military, read the report.

“BLA is prepared for a prisoner exchange,” the group said.

“If our demands are not met within the stipulated period or if the occupying state attempts any military action during this time all prisoners of war will be neutralized and the train will be completely destroyed.”

The group, which seeks independence for Balochistan province bordering both Afghanistan and Iran, said the hostages included Pakistan Army members and other security officials travelling on leave.

Dilawar said some of the militants had taken a group of around 35 hostages into the mountains while others were still holding the locomotive. He had previously said that over 300 hostages were safe but security officials have since announced that 104 people have been rescued so far, Reuters reported.

Security forces said an explosion had been heard near the tunnel and that they were exchanging fire with the militants in a mountainous area.

A security source who asked not to be identified said many people had lost their lives in the attack, adding that 80 military personnel were among the 425 passengers aboard the train.

Another security source said 104 passengers had been rescued, 17 wounded taken to hospital and 16 militants had been killed, adding the rest were surrounded.

“The operation will continue until the last terrorist is eliminated,” they said.

The BLA said it has not suffered any casualties. It said it had killed 30 soldiers and shot down a drone. There was no confirmation of that from Pakistani authorities.

Pakistani Prime Minister Shehbaz Sharif condemned the attack, saying security officials were “repelling” the militants.

“Civilian passengers, particularly women, children, the elderly, and Baloch citizens, have been released safely and given a secure route,” the BLA said in a statement emailed to journalists and posted on Telegram.

“The BLA further warns that if military intervention continues, all hostages will be executed.”

The Jaffar Express had been on its way from Balochistan’s capital, Quetta, to the city of Peshawar in Khyber Pakhtunkhwa province when it was fired on.

Pakistani Interior Minister Mohsin Naqvi condemned the attack and praised the military for rescuing more than 100 passengers.

“Those who attack innocent passengers are enemies of the country,” he said.

“Enemy forces are conspiring to create instability in the country through terrorism in Balochistan.”

The Balochistan government has imposed emergency measures to deal with the situation, spokesperson Shahid Rind said, without giving any more details.

The BLA is the biggest of several groups that have been battling the government for decades, saying it unfairly exploits Balochistan’s rich gas and mineral resources, read the report.

The conflict has seen frequent attacks against the government, army and Chinese interests in the region.

The Kremlin, asked on Monday if Russia had held consultations with Iran before or after Tehran responded to a letter from U.S. President Donald Trump urging the country to negotiate a nuclear deal, said Iran formulates its own policy positions.

Iran’s Supreme Leader Ayatollah Ali Khamenei said on Saturday that Tehran would not be bullied into negotiations, a day after Trump said he had sent a letter urging Iran to engage in talks on a new nuclear deal.

Asked if Moscow had consulted with Tehran before or after Trump’s letter, Kremlin spokesman Dmitry Peskov told reporters:

“No. Iran is a sovereign country and independently formulates its position on key foreign policy issues. It is clear that very tense contacts are ahead.”

Trump has previously said he would reimpose a policy of “maximum pressure” on Iran, aimed at preventing the country from building nuclear weapons, even as he has signalled openness to a new nuclear accord with Tehran.

Russia and Iran have drawn closer since the start of the war in Ukraine, with Tehran providing Moscow with drones.

Regarding possible talks on Tehran’s nuclear program, Peskov said: “It is clear that Iran is seeking negotiations based on mutual respect, constructive negotiations.”

“We, of course, for our part, will continue to do everything that depends on us, everything that is possible, in order to bring this process of settling the Iranian nuclear dossier into a peaceful direction.”

Supreme Leader Ayatollah Ali Khamenei said on Saturday that Iran will not be bullied into negotiations, a day after U.S. President Donald Trump said he had sent a letter to the country’s top authority urging Tehran to negotiate a nuclear deal.

In an interview with Fox Business, Trump said, “There are two ways Iran can be handled: militarily, or you make a deal” to prevent Tehran from acquiring nuclear weapons.

At a meeting with senior Iranian officials, Khamenei said Washington’s aim was to “impose their own expectations,” Iranian state media reported.

“The insistence of some bullying governments on negotiations is not to resolve issues. … Talks for them is a pathway to have new demands, it is not only about Iran’s nuclear issue. … Iran will definitely not accept their expectations,” Khamenei was quoted as saying, without directly mentioning Trump.

In response to Khamenei’s comments, White House National Security Council spokesman Brian Hughes reiterated almost word for word the choice of negotiations or military action that Trump said he had presented to Iran.

“We hope the Iran Regime puts its people and best interests ahead of terror,” Hughes said in a statement.

While expressing openness to a deal with Tehran, Trump has reinstated a “maximum pressure” campaign that was applied during his first term as president to isolate Iran from the global economy and drive its oil exports to zero.

During his 2017-2021 term, Trump withdrew the United States from a landmark deal between Iran and major powers that had placed strict limits on Tehran’s nuclear activities in exchange for sanctions relief.

After Trump pulled out in 2018 and re-imposed sanctions, Iran breached and far surpassed those limits.

U.N. nuclear watchdog chief Rafael Grossi has said that time is running out for diplomacy to impose new restrictions on Iran’s activities, as Tehran continues to accelerate its enrichment of uranium to near weapons-grade.

Tehran says its nuclear work is solely for peaceful purposes.

Khamenei, who has the last say on Iran’s key policies, said there was “no other way to stand against coercion and bullying”.

“They are bringing up new demands that certainly will not be accepted by Iran, like our defence capabilities, missile range and international influence,” he was quoted as saying.

Although Tehran says its ballistic missile programme is purely defensive, it is seen in the West as a destabilising factor in a volatile, conflict-ridden Middle East.

Tehran has in recent months announced new additions to its conventional weaponry, such as its first drone carrier and an underground naval base amid rising tensions with the U.S. and Israel.