Palestinian security forces arrested on Tuesday a suspect in the killing of Israeli actor Juliano Mer-Khamis in Jenin on Monday.

According to a security official, Palestinian police have been probing the man - a former al-Aqsa Martyr Brigades militant who was released from Israeli prison more than five years ago - but he has yet to confess to the murder.

Mer-Khamis, 53, an Israeli actor and political activist was shot dead on Monday outside a theater which he founded in a refugee camp in the West Bank city of Jenin.

Jenin police Chief Mohammed Tayyim said Mer-Khamis was shot five times by masked Palestinian militants. Israeli security forces are also investigating the circumstances of his murder.

Mer-Khamis was affiliated with a local theater in Jenin, established by his mother in the 1980s. In 2006, Mer-Khamis opened the Freedom Theater in Jenin, along with Zakariya Zubeidi, the former military leader of the Al-Aqsa Martyr Brigades in the West Bank city.

Zubeidi said in a press conference held at the Freedom Theater on Tuesday that he believed that either a country or organization was behind the murder of his friend.

He said the masked killer seemed to have been trained and that they shot Mer-Khamis in the chest and head seven times.

The Freedom Theater had faced threats before; it was torched twice in the past, and the threats persisted despite Zubeidi's appointment.

Some of the criticism focused on the fact that the theater offered co-ed activities, despite prohibition in the Islamic moral code.