Freed Hamas MP Hatem Qafisheh (L) with parliament speaker Aziz Dweik

Israel has released six members of the Palestinian parliament from jail after holding them for up to three years.

Some of those who were freed, who were members of Hamas, were never charged with an offence.

Israel arrested 45 Hamas MPs in the occupied West Bank after the group's military wing in Gaza captured Israeli soldier, Gilad Schalit in 2006.

Israeli officials say the Hamas MPs had completed their prison terms and were not part of a prisoner-swap.

About 20 Palestinian parliamentarians remain in Israeli custody, including at least 15 from Hamas.

Many of them are held under Israeli administrative detention rules, which allow detainees to be held indefinitely without charge.

Hamas won overall control of the Palestinian parliament in the 2006 elections, beating the Fatah party of Palestinian Authority leader Mahmoud Abbas.

They seized the Gaza Strip in 2007, while the West Bank has remained under the authority of Mr Abbas.

Mr Abbas has called for fresh elections in January 2010, but Hamas has warned Gaza residents not to participate. They say Mr Abbas does not have the authority to call the vote because his presidential term has already ended.

Israel released 20 female Palestinian prisoners in October 2009 in return for video evidence that Gilad Schalit was alive.