Israel's army early Wednesday arrested five members of Palestinian Islamist group Hamas, including a member of parliament, a prisoners' support group said.
The five were arrested at dawn at their homes in the southern West Bank city of Hebron, the Ramallah-based Prisoners' Club told AFP.
They included Hamas MP Mohammed Jamal al-Natshe, it said.
An Israeli army spokeswoman said that "six people were arrested and taken for security questioning," but gave no further details.
Israel has stepped up arrests of Hamas members in the West Bank, in part to prevent a rising tide of low-intensity conflict and civil unrest from turning into an uprising.
Hamas has 74 members in the 132-seat Palestinian Legislative Council, which is based in Ramallah.