Israeli forces hit the city of Jenin with drone strikes on Monday in one of the biggest West Bank operations in 20 years, killing at least eight Palestinians and involving hundreds of troops in sporadic gun battles that continued into the evening.

Gunfire and explosions were heard throughout the day as clashes continued between Israeli troops and fighters from the Jenin Brigades, a unit made up of militant groups based in the city's crowded refugee camp.

"What is going on in the refugee camp is real war," said Palestinian ambulance driver Khaled Alahmad. "There were strikes from the sky targeting the camp, every time we drive in, around five to seven ambulances and we come back full of injured."

At times during the morning, at least six drones could be seen circling over the city and the adjoining camp, a densely packed area housing around 14,000 refugees in less than half a square kilometre.

The camp has been at the heart of an escalation of violence across the West Bank that has triggered mounting alarm from Washington to the Arab world, without so far opening the way to a resumption of political negotiations that have been stalled for almost a decade.

For more than a year, army raids in cities such as Jenin have become routine, while there have been a series of deadly attacks by Palestinians against Israelis and rampages by Jewish settler mobs against Palestinian villages.

The Palestinian health ministry confirmed at least eight people had been killed and more than 50 wounded in Jenin, while another man was killed in Ramallah overnight, shot in the head at a checkpoint.

The Israeli military said its forces struck a building that served as a command centre for fighters from the Jenin Brigades with what it called "precise" drone strikes using small payloads. It described the operation as an extensive counter-terrorism effort aimed at destroying infrastructure and disrupting militants from using the refugee camp as a base.

As the operation proceeded, Israeli armoured bulldozers ploughed up roads in the camp to dig up concealed improvised explosive devices, cutting water and electricity supplies, the Jenin municipality said as residents described soldiers breaking through the walls to pass from house to house.

"Nothing is safe in the camp. They dug up the roads with bulldozers. Why? What did the camp do?" said Hussein Zeidan, 67, as he recovered from his wounds in hospital.