Exiled Hamas leader Khaled Meshaa made his first-ever visit to the Gaza Strip on Friday for festivities marking the ruling movement's 25th anniversary.
The visit reflected a growing confidence in Palestinians in their relationship both with Israel and with their Egyptian neighbours.
He arrived in Gaza through the Rafah crossing with Egypt and held a news conference before travelling to Gaza City to visit the home of Hamas founder Sheikh Ahmed Yassin, who was assassinated by Israel in 2004.
Islamic Jihad chief Ramadan Shallah had also been expected to attend the anniversary celebrations, but he cancelled the trip over Israeli threats to end the ceasefire if he came to Gaza.
Hamas marks its official anniversary on December 14, but celebrations are set to begin earlier with a major rally yesterday.
The rally is not being held on the exact date of Hamas's founding, but on the 25th anniversary of the first intifada.
That is being seen as a hint of a new willingness to seek reconciliation with Palestinian President Mahmoud Abbas's Fatah movement.
"There is a new mood that allows us to achieve reconciliation," Meshaal said in an interview last Friday.
Elsewhere, Human Rights Watch accused Israel of violating the laws of war when it killed 12 civilians in an air strike last month.
Israel claimed that it launched its air assault on Gaza to try to stop frequent rocket barrages at southern Israel.
But when the attacks ended after eight days, airstrikes had been focused on individual homes as much as supposed rocket sites.
The Israeli airforce attacked the home of the Daloo family in Gaza City, killing 10 family members and two other civilians.
An Israeli spokesman initially claimed it was targeting a senior member of Hamas Yahia Abayah, but later announced that the air strike had killed Mohammed Daloo and tagged him a Hamas militant.
However Human Rights Watch said that Mr Daloo was simply a low-ranking police officer.
"Even if he was a legitimate military target, the likelihood that the attack on a home would have killed large numbers of civilians made it unlawfully disproportionate," it said.
