An Interior Ministry spokesman said the four men, who were executed on Sunday, were sentenced to death by a Palestinian court.

Spokesman Tawfiq Abu Khoussa added that Palestinian President Mahmoud Abbas signed the execution orders on Saturday.

Three of the men were hanged and one was executed by a firing squad.

The Palestinian Authority has had the death penalty in place since its establishment in 1994.

However, late president Yasser Arafat halted the death penalty in 2001 after criticism by international human rights groups.

Sunday's executions approved by Abbas, under intense internal pressure to stamp out rampant crime, appeared to be an attempt to deter criminals and send a message to the public without confronting resistance groups.

"There is a new policy of enforcing the law, to face and fight the chaos and lawlessness in the Palestinian territories," Abu Khoussa said.

Fifty-one Palestinians are on death row, about half of them alleged collaborators with Israel.

Palestinian officials said last month that they had suspended plans to execute the collaborators, fearing their deaths would inflame tensions with Israel.