"Each of these adversaries is capable of sparking a war in the summer," Yadlin was quoted as saying.

[On Monday, Al Qaida's No. 2 Ayman Zawahiri endorsed the Hamas takeover of the Gaza Strip, Middle East Newsline reported. The Al Qaida statement came after Zawahiri repeatedly criticized Hamas for tolerating Palestinian Authority cooperation with the United States.]

Yadlin said Hamas could be planning a major attack to divert attention away from efforts by the Palestinian Authority to isolate the Gaza Strip. He said Syria might be promoting such an attack.

Officials said Iran has direct influence over Syria, Hizbullah and Hamas. He said Al Qaida has increasingly come under Iranian influence and was being used by Iran and Syria in such countries as Iraq, Jordan and Lebanon.

Already, military intelligence has assessed that Hamas acquired more than 50 missiles with a range of 22 kilometers. Officials said this would allow Palestinian missile strikes on any part of Ashkelon, the largest city in southeastern Israel and which contains strategic sites.

Hamas has also deployed at least 20 SA-7 anti-aircraft systems, officials said. They said the missiles threaten Israeli combat helicopters and fixed-wing aircraft that conduct missions over the Gaza Strip.

On Monday, Palestinian gunners continued missile fire into Israel. Hours earlier, the Israel Air Force struck an Islamic Jihad squad said to have been driving toward the northern Gaza Strip to launch missiles toward Israel. One Jihad operative was killed and two others were injured.

Israeli military intelligence has assessed that Hamas was being quietly supported by neighboring Egypt. Officials said that despite Egypt's announced ban, Cairo has continued to allow Hamas leaders to enter the Sinai Peninsula from the Gaza Strip.

Over the weekend, officials said, a Hamas delegation led by former PA Interior Minister Said Siyyam entered Sinai. They said the 15-member delegation was escorted by Egyptian security forces to Cairo for a flight to Damascus, where they were scheduled to meet Hamas political bureau chief Khaled Masha'al.

On Monday, Egypt was scheduled to host a regional summit meant to support PA Chairman Mahmoud Abbas. Israel, Jordan and Abbas were expected to attend the meeting in the Sinai resort town of Sharm e-Sheik.