Palestinian gunmen seized the governor's office in a southern city on Sunday, demanding aid for families left homeless by an Israeli military operation, witnesses said.

It was the latest case of violence directed toward Yasser Arafat's (search) Palestinian Authority, widely accused of corruption and ineffectiveness.

About 15 gunmen from the Al Aqsa Martyrs' Brigades (search), a militant group with loose ties to Arafat's Fatah (search) movement, seized the governor's office in Khan Younis early Sunday, expelling workers from the building, witnesses said.

The governor was not in the office at the time but the militants were negotiating with him by phone, one of the gunmen told The Associated Press.

Israeli troops destroyed two apartment buildings in Khan Younis last Thursday, leaving 40 families homeless, Palestinian residents said. The army said the buildings provided cover for militants and were largely uninhabited.

In recent weeks, there has been a series of kidnappings, shootings, and other attacks against members of the Palestinian Authority.