Armed militants abducted 13 Coptic Christians from Egypt in Libya late Saturday, only a week after seven others were kidnapped from a Libyan city overrun with Islamist extremists. 

The masked gunmen stormed a Sirte city residential building in the dead of night and demanded to see the residences' identification papers to determine who was Muslim and who was Christian, witness Hanna Aziz told the Associated Press.

"They were 15 armed and masked men who came in four vehicles," Aziz, whose three family members were kidnapped, told the AP. "They had a list full of names of Christians in the building. While checking IDs, Muslims were left aside while Christians were grabbed."

Once the Egyptian Christians were singled out, the gunmen handcuffed them and drove away.

"I am still in my room waiting for them to take me. I want to die with them," the witness said.

The abductions are the latest in an uptick in violence carried out against Coptic Christians working in conflict-torn Libya. Islamist militants have carried out attacks on Christians, women and people accused of being loyalists to the African nation's ousted leader Moammar Gadhafi, the AP reported. He was killed in 2011.

Just a week ago, seven other Egyptian Christians from Samalout were abducted before they were able to flee Sirte, where the militants had found a save haven. A Coptic couple and their daughter were also recently killed.

Last March, seven Coptics were found shot to death and handcuffed in the eastern city of Benghazi, the AP reported. Officials also say militants are targeting Egyptians in retaliation for Egypt's government supporting Libya's army for fighting the extremists.

"We are witnessing a pattern of persecution against Christians in Egypt," Magdi Malak, an Egyptian activist involved in the case, told the news agency. "I fear for the lives of the hostages."

Egypt's government has not immediately commented on the latest kidnappings. Its Foreign Ministry said last Wednesday it's investigating the seven kidnapped a few days ago.