Relatives identified the dead man as Khodr al-Husari, a member of the Izz al-Din al-Qassam Brigades, the armed wing of Hamas.
The missiles, fired from US-supplied Apache helicopters, slammed into a car in the central sector of the city.
It was Israel's sixth helicopter attack against Palestinian resistance activists in the past two weeks.
Israel has killed 11 Hamas activists and three civilians in recent helicopter missile attacks in the Gaza Strip.
West Bank clashes
Meanwhile, Israeli soldiers have opened fire on Palestinian teenagers, injuring at least 16, one seriously, in the occupied West Bank city of Nablus.
The teens were protesting on Monday against Israel's crippling blanket curfew over the city, when soldiers opened fire with live and rubber bullets, according to medical sources.
One of them was hit in the head.
Occupation forces had tightened the closure in Hebron, which entered its sixth day, sealing off virtually all entrances to the city.
Palestinian authorities and Israeli occupation soldiers reached an agreement allowing schoolchildren in the occupied West Bank city of Hebron to go to schools for the first day of term, despite the closure.
Busses were seen ferrying thousands of students after Israeli troops said they would allow students and teachers to go to schools, reported our correspondent in Hebron.
It is the first time Israeli occupation authorities have reached a settlement with Palestinians allowing students and teachers to go to schools under a curfew since the start of the Intifada in September 2000, said Aljazeera’s Wail al-Shuyukhi.
Palestinian students cross army
roadblocks to get to school
“But this does not mean they will be allowed to go to school tomorrow,” he added, stressing the Palestinian side had struggled to ensure all students were enrolled on the first day.
During the evening, armed Jewish settlers harass civilians who venture out to buy supplies. Israeli soldiers do not intervene.
Nasr Kawasami runs a shoe factory with his extended family in Hebron and lamented the closure prevented his labourers from reaching the factory on Sunday.
“Our situation is miserable,” said Nasr Kawasami, adding business has sharply dwindled over the past nine months as Israeli occupation forces have increasingly imposed curfews.
While his two children, aged seven and four, joined other children in going to school, businesses and petrol stations remained firmly shut, he said.
At the end of the 2002-2003 school term Israel imposed curfews across the West Bank, preventing thousands of students from doing their final examinations.
Also, Israeli bulldozers overnight destroyed the family home of an activist held responsible for a series of resistance attacks.
Soldiers detained a man they claimed was a Hamas chief. Local residents said he was a blacksmith who was a pious Muslim.
Meanwhile, accompanied by a bulldozer and opening fire, the Israeli army has invaded Deir al-Balah refugee camp in the occupied Gaza Strip.
Israeli soldiers also erected roadblocks on the main road through the Gaza Strip. The military said Palestinian activists had fired four rockets from the southern Gaza Strip to the Neve Dekalim Jewish settlement, without causing injuries.
On the diplomatic front, European Union Foreign Policy Chief, Javier Solana, was expected to hold talks with Israeli Prime Minister, Ariel Sharon, late on Monday.
Solana, who flew to Jordan on Monday for meetings with officials, is expected to urge Israel to resume contacts with the Palestinians and warn them about the impact of assassinations of Hamas activists, said an EU spokeswoman.
“The position of the European Union is that these types of actions (targeted killings) are not conducive to building more confidence and trust and you should try to avoid them,” said spokeswoman Cristina Gallach.
In the past month Israel has killed 10 Hamas activists, shattering a unilateral truce agreed by resistance groups.