Gaza City, Gazy Strip ? The top Palestinian security official quit in exasperation Monday after a second day of firefights among Palestinian factions left four more people dead, including a truck driver delivering bread.

Residents frightened by the upsurge in violence holed up in their homes, leaving Gaza City’s streets largely deserted while rival security forces took up positions on rooftops and hundreds of gunmen in black ski masks put up checkpoints and stopped cars. Eight people were killed and 70 wounded Sunday and Monday.

The 2-month-old Hamas-Fatah unity government struggled to prevent Gaza from again descending into chaos, reaching an agreement with warring factions for a truce late Monday, the second such agreement in as many days, government spokesman Ghazi Hamad said.

But rival sides continued to battle each other throughout the night, leaving one Hamas man dead in fighting early today, Palestinian security officials said.

With the casualty toll mounting, Interior Minister Hani Kawasmeh resigned and accused leaders on both sides of thwarting his efforts to halt the violence.

The career civil servant was a compromise candidate for the top security post when the Fatah movement and the Islamic radicals of Hamas formed a unity government in March after months of factional fighting. His resignation was a new blow to the shaky coalition.

Gazans found the latest violence more ominous than the previous round, saying it signaled the failure of the power-sharing deal between Hamas and Fatah.

“Now they are starting from where they left off,” said Jamal Abu Shabaan, 21, who witnessed a gunbattle Sunday outside his furniture store. “If they get to each others’ throats, they won’t let go this time.”

Abu Shabaan said he had made up his mind after the last round of bloodshed to emigrate to Saudi Arabia and expected to leave in the coming days.

Universities were closed because of the violence, and many worried parents kept their children home from school.

At the center of the new Palestinian fighting is a dispute over who controls the security forces. A majority of the 80,000 security officers in the West Bank and Gaza are loyal to moderate Palestinian President Mahmoud Abbas, the Fatah leader, while Hamas set up its own 6,000-strong militia last year.

Two weeks ago, Kawasmeh threatened to resign, complaining his security plan was ignored.