The camp is heading in a catastrophic direction, says UNRWA spokesperson Juliette Touma to a press gathering at the UN headquarters in Geneva, Switzerland, according to AFP.
Large parts of Jenin have been completely destroyed "in a series of detonations carried out by the Israeli forces", according to Touma.
Beside a fragile ceasefire in Gaza, Israel has launched new attacks in the other Palestinian area, the West Bank, which has been under Israeli occupation for several decades.
Palestinian authorities have warned that at least 20 people have been killed. Tens or hundreds are reported to have been arrested. Israel claims to be responding to a "military development" on the West Bank and claims that at least 50 opponents referred to as terrorists have been killed.
Two Israeli soldiers were shot dead in an attack on a military checkpoint on the northern West Bank on Tuesday morning, the Israeli military reports. The perpetrator is said to have been killed.
The Palestinian news agency Wafa reports that Israeli authorities have brought in bulldozers and demolished buildings in Palestinian agricultural areas, including near illegal Israeli settlements.