Hamdallah, who is a member of the internationally-backed Palestinian Authority (PA) in the West Bank, continued his trip into Gaza following the blast to give a speech at the opening ceremony of a waste treatment plant.
Nobody immediately claimed responsibility for the attack, which left three vehicles damaged and six security guards injured.
Hamdallah immediately returned to the West Bank after delivering the speech, vowing to continue reconciliation efforts with rival Palestinian group Hamas in Gaza.
"This will not deter from seeking to end the bitter split. We will still come to Gaza," he said.
Read more: What are Fatah and Hamas?
Responsibility unclearPA President Mahmud Abbas said he held Hamas responsible for the attack. But his security chief, Majed Farraj, said it was too early to say whether Hamas had been involved.
Hamas, which condemned the attack, said it considered the attack as an attempt to block a Palestinian unity agreement drawn up in October. Hamas security forces said they launched an investigation into the attack.
Gaza, which is separated from the West Bank by Israeli territory, has been controlled Hamas since the militant group ousted the PA in 2007. Several other militant groups also operate in Gaza.
Read more: Israel airstrikes strike Gaza Strip during Palestinian 'day of rage'
Hamas' troublesHamas has fought three wars with Israel and Gaza has suffered from a devastating Israeli and Egyptian blockade.
Egyptian-backed reconciliation talks between Hamas and the PA have stuttered since Hamas handed over control of Gaza's border crossings to the PA in November.
Hamas' police force and armed wing, which the US and the European Union consider a terrorist organization, continues to have full control of the rest of Gaza. Hamas has refused to disband its miltary wing and hand over security to the PA as part of a reconciliation deal.
Read more: US designates Hamas leader Ismail Haniyeh an international terrorist
White House meeting on GazaThe US is set to discuss the dire humanitarian situation in Gaza during a White House meeting later on Tuesday.
It is unclear whether PA representatives will attend the meeting, since the PA has boycotted US officials in response to the US' recognition of Jerusalem as Israel's capital city in early December.
Read more: Hamas calls for third intifada after US recognizes Jerusalem as Israel's capital
cw, amp/rc (Reuters, AP, AFP)
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