Masked gunmen in central Libya kidnapped 13 Coptic Christians on Saturday after seven were abducted days earlier, said a witness and a priest, in a new wave of assaults against Egypt’s Christians working in the war-torn North African nation.

Witness Hanna Aziz said 15 gunmen in the Libyan city of Sirte went room to room in a residential compound at 2:30 a.m. Saturday. Aziz said the assailants asked for identification papers to separate Muslim workers from Christians, who they handcuffed and drove away with.

“They had a list of full names of Christians in the building. While checking IDs, Muslims were left aside while Christians were grabbed,” Aziz said, adding that he wasn’t taken simply because he didn’t open his door.

“I heard my friends screaming, but they were quickly shushed at gunpoint. After that, we heard nothing,” said Aziz, who has three relatives among the hostages. “I am still in my room waiting for them to take me. I want to die with them.”

Abu Makar, a Coptic priest in the workers’ home town of Samalout in southern Egypt, confirmed the abduction took place. He said seven other Coptic Christians from Samalout were taken while trying to escape Sirte a few days earlier.

Sirte has become a safe haven for extremist Islamist groups such as Ansar al-Shariah, blamed for the Sept. 11, 2012, attack on the U.S. diplomatic mission in Benghazi that killed U.S. Ambassador J. Christopher Stevens and three other Americans.

The Egyptian Foreign Ministry said in a statement that it is following up on the abduction case, urging Egyptians in the city to stay indoors until the government can facilitate a safe return home. Ministry spokesman Badr Abdel-Atti said that Egypt can’t send a diplomatic mission to Libya because “many of the regions are out of state control.” Egypt closed its mission in Tripoli last year and withdrew its ambassador after his own abduction at the hands of militiamen, disgruntled at the arrest of a top Islamic militia commander in Egypt.

The recent abductions come on the heels of the killing of a Coptic couple — who used to work as doctors in Sirte— and their daughter.

Islamic extremist militias have been targeting Christians, women, journalists, refugees and those considered former loyalists of Moammar Gadhafi, who was toppled and killed in Libya’s 2011 civil war.

Last February, the bodies of seven Christian Egyptians were found in Benghazi, shot in the head while handcuffed. In March 2013, dozens of Coptic Christians were tortured inside a detention center run by a powerful militia in Benghazi. The men, who were suspected of proselytizing, were rounded up in a market by gunmen who checked their right wrists for tattoos of crosses, a common mark worn by many Egyptian Christians.

“We are witnessing a pattern of persecution against Christians in Egypt; I fear for the lives of the hostages,” said Magdi Malak, a Cairo-based activist involved in the case.

— Associated Press