Hamas security officials in Gaza on Sunday arrested the spokesman of a Palestinian militant group that claimed responsibility for a rocket attack on Israel in violation of a truce, the manÂ’s family said. Muhammad Abu Irmana, the spokesman for the Al-Aqsa Brigade, was visiting his relatives in the southern Gaza town of Rafah when he was detained, his brother Adham said. Irmana, also known as Abu Qusai, was arrested because the armed group, which is loosely linked to the Fatah party of Palestinian President Mahmud Abbas, said it was behind two rocket attacks on Israel on Thursday, Adham said.