JERUSALEM, April 10 (Xinhua) -- The Hamas movement has increased its militia to some 20,000 gunmen and now is able to carry out complex attacks, an Israeli intelligence organization said a report issued Thursday.

    The current size of the movement's forces is estimated at20,000 armed operatives who are directly subordinate to the group or can be integrated into its forces in an emergency, said a report by the Intelligence and Terrorism Information Center at Israel intelligence Heritage and Commemoration Center.

    The group is now equipped with advanced weapons, including improved rockets and advanced anti-tank missiles, with "improved capabilities to carry out complex terrorist attacks such as mass-casualty attacks and the abductions of soldiers and civilians," said the report published on the organization's web site.

    Hamas, ruler of the Gaza Strip, has accelerated its military build-up since Israel's unilateral disengagement from the area in 2005, and particularly during the past year, the report said, while pinpointing Syria and Iran as key supporters of the group.

    The report came a day after two civilians were killed inside a border terminal by Palestinian militants from Gaza Strip, for which senior Israeli officials have vowed to hold Hamas responsible.

    An Israeli soldier was also killed Tuesday night by Palestinian ambush in southern Gaza Strip.