NABLUS, West Bank (AP) — Palestinian security forces in the West Bank have stopped torturing Hamas prisoners, ending two years of systematic abuse, Hamas inmates said in jailhouse interviews.

The change in practice, said to have taken effect in October, was confirmed by a West Bank Hamas leader, human rights activists and the Palestinian prime minister. Prime Minister Salam Fayyad said the decision to halt any abuse was part of an effort to make sure a future state is built on the right foundations.

Hamas legislators and human rights researchers said the worst behavior — prisoners beaten with clubs and cables; suspended from the ceiling while tied up in painful positions; and forced to stand for days — had ended.

But they said they still received sporadic reports of prisoners being slapped or forced to stand for several hours during interrogations. And security forces often arrest Hamas activists and hold them for lengthy periods without charge.

Mr. Fayyad confirmed a “dramatic change for the better” in West Bank prisons and said that 43 officers had been jailed, fired or demoted for abusing prisoners. In an interview, he denied that torture was ever official policy but acknowledged past “excesses” that he said stemmed from a flawed culture of revenge. He said interrogations could be done legally. “If that means we get less information, so be it,” he said.

Palestinian security forces under President Mahmoud Abbas, dominated by supporters of his Fatah movement, have been clamping down on Hamas in the West Bank since June 2007, when Hamas wrested control of the Gaza Strip from the Palestinian leader. Since then, about 4,000 Hamas followers have been arrested in the West Bank, and 500 are in detention, according to Hamas. In Gaza, Hamas has rounded up hundreds of Fatah supporters, who have also complained of severe mistreatment.

In the West Bank, persistent reports of abuse emerged in the past two years from prisons and interrogation centers. Since 2007, 8 detainees have died in jails in the West Bank and 15 in Gaza, human rights researchers say, though circumstances in some cases remain murky.

The abuse was driven both by a desire to take revenge for the Gaza takeover and by fear that Hamas would seize control of the West Bank, said Salah Mousa, a human rights activist and former member of the Palestinian security forces. The worst accounts of abuse came from Jneid Prison, a barbed-wire-topped jumble of low buildings in Nablus, a former Hamas stronghold. Last week, inmates there, speaking while wardens were out of earshot, described past abuse and said that it had largely stopped.

Khaled Susah, 48, at Jneid for the past 14 months, pulled back a sleeve to show a swollen right wrist, which he said was the result of being repeatedly handcuffed and strung up from the ceiling during 80 days of interrogation at the start of his detention. “They were dealing with us like sheep in a slaughterhouse,” Mr. Susah said.