Palestinian leader Mahmoud Abbas has met militant representatives in Gaza in an attempt to prevent the collapse of a fragile ceasefire with Israel.
Abbas wanted a pledge from militants not to respond every time
The militants, including Islamic Jihad and Hamas, undertook to uphold the truce - but said they would continue responding to any Israeli attacks.
Israeli warplanes broke the sound barrier over Gaza throughout the talks.
In the latest flare-up, Israel killed two Palestinians in the West Bank and militants attacked a Gaza settlement.
Two Palestinian and one Chinese farm worker were killed in the attack at the Jewish settlement in southern Gaza.
The BBC's Jerusalem correspondent, Barbara Plett, says both sides offer different explanations for the strain on the ceasefire, accusing the other of violations.
Israel launched a brief incursion into Gaza late on Wednesday night and earlier fired a missile at a car carrying Hamas members - although no-one was hurt in the air strike.
On arriving in Gaza from Ramallah in the West Bank, Mr Abbas criticised the Israeli air strike as "an unjustified operation" that "will destroy the truce".
Our correspondent says the Palestinian Authority's dealings with the militants have deteriorated since Mr Abbas announced the indefinite postponement of parliamentary elections scheduled for July.
Hamas had been planning to contest the polls and capitalise on dissatisfaction with the administration.
During his three days in Gaza, Mr Abbas will also try to smooth over differences of opinion with Hamas - whose top leaders in the territory were not present at Thursday's meeting.
Earlier Hamas leader Mahmoud al-Zahar told the BBC that Mr Abbas' visit was a pointless exercise and ignored the fact that Israel was "violating all the principles of the truce".
Israeli aircraft on Wednesday fired at militants in the Gaza Strip but the targets of the attack escaped unhurt, witnesses said.
The Israeli military said it targeted a mortar launcher and a vehicle carrying mortar shells near Khan Younis.
Hamas said that both the vehicle targeted on Wednesday and the people nearby were its members.
A Palestinian taxi driver falls foul of Israeli troops in Gaza
They managed to escape before the explosion, witnesses said.
Separately, Israel and Palestinian officials say they have agreed to co-operate closely on ensuring calm prevails during the Gaza pullout later this year.
Israel's Defence Minister, Shaul Mofaz, met Palestinian Interior Minister Nasser Youssef to discuss joint security measures.
The Israeli defence ministry said "co-ordination in the field" would ensure Palestinians could deploy their security forces to prevent militants from taking over in areas vacated by Israel.
Israel is planning to pull all 8,000 Jewish settlers out of the Gaza Strip and the troops that protect them this summer. It will maintaining control of Gaza's borders, coastline and airspace.