JENIN, West Bank (Reuters) -Israeli commandos backed by a military helicopter killed three Palestinians, including a teenager, and wounded at least 29 others during a fierce clash in the occupied West Bank on Monday, local gunmen and medical officials said.

Israel's military said it had launched the raid on Jenin to detain Palestinians suspected of attacks and that troops had exchanged fire with gunmen, hitting several of them.

Video obtained by Reuters showed an explosion enveloping an armoured troop carrier as shots ring out. Another clip showed what appeared to be an Israeli helicopter launching a missile.

The military statement confirmed that a helicopter had opened fire during the clash and that one of its vehicles had been hit by a blast. It did not immediately comment on media reports that five soldiers were wounded in the latter incident.

The Palestinian health ministry said the three dead males included a 15-year-old. There was no immediate word on whether any of them were affiliated with Palestinian armed groups.

One such group, Islamic Jihad, said it was taking part in the clashes in Jenin, among areas in the northern West Bank that has seen intensified raids by Israel over the past 15 months amid a spate of Palestinian street attacks in its cities.

At least one Palestinian was detained during Monday's raid, witnesses in Jenin said.

(Writing by Dan Williams and Nidal al-MughrabiEditing by Gareth Jones)