Israeli forces have killed three Palestinians, including a teenager, and fired missiles from a helicopter during a raid on the occupied West Bank that the army said was to pursue "wanted suspects".
"Three Palestinians died as a result of the occupation (Israeli) aggression on Jenin," a statement from the Palestinian health ministry said, adding that at least 29 others were wounded.
It named the three killed as Qassam Abu Saria, aged 29, Khaled Assassa, aged 21, and Ahmed Saqer, aged 15.
The Israeli army said a "massive exchange of fire" erupted as forces entered the northern West Bank city to arrest "wanted suspects".
"IDF (army) helicopters opened fire toward the gunmen in order to assist in extraction of the forces" after "large numbers of explosive devices were hurled at the forces", it added in a statement.
The army said a military vehicle had been damaged by an explosive device.
A Palestinian intelligence official said, on condition of anonymity, it was the first time since 2002 - during the second Palestinian intifada, or uprising - that the Israeli army has fired missiles from an aircraft during a raid in Jenin.
A photographer in the city, the scene of frequent clashes between Israeli forces and Palestinian militants, confirmed that fighting was ongoing as of 10.30am (08.30am Irish time).
Jenin's deputy governor Kamal Abu al-Rub said the Israeli forces had launched the raid at around 4am (2am Irish time).
"The army stormed the (Jenin refugee) camp and the city after the dawn prayer in large numbers, and there was intense gunfire," he said.
Hussein al-Sheikh, the Palestinian Authority's civil affairs minister, said a "fierce and open war is being waged against the Palestinian people... by the occupation (Israeli) forces".
He called for the Palestinian leadership to take "unprecedented decisions" without elaborating.
Israel has occupied the West Bank since the 1967 Six-Day War and its forces regularly launch incursions into Palestinian cities, which are nominally under the control of president Mahmud Abbas's Palestinian Authority.
Jenin and its adjacent refugee camp have frequently been the site of violent clashes between Israel and the Palestinians.
In March, four Palestinians were killed during the a raid on the camp.
Ten Palestinian were killed in another operation in the camp in January - the deadliest single raid in the West Bank for 20 years.
Since the start of the year, at least 162 Palestinians, 21 Israelis, a Ukrainian and an Italian have been killed in violence linked to the Israeli-Palestinian conflict, according to an AFP tally compiled from official sources.
The figures include combatants as well as civilians and, on the Israeli side, three members of the Arab minority.
