A senior Palestinian official has been seriously injured in an assault by a gang of masked gunmen.
Gunmen stormed a government building in Gaza recently
Ibrahim Salama was driving in the West Bank city of Ramallah when gunmen fired at his car to force him to stop, an interior ministry statement said.
Mr Salama was severely beaten "with a sharp object" and taken to hospital.
It is the latest in a series of incidents believed to be part of a power struggle within the mainstream Fatah movement.
Dozens of members of al-Aqsa Martyr's Brigade, an armed offshoot of Fatah, stormed a government building in Gaza 10 days ago demanding Palestinian leader Mahmoud Abbas make good on a promise to recruit them into the security forces.
Mr Abbas described the assault on Mr Salama as "outrageous".
"The security services will take immediate and serious action and will chase after those involved. We will deal with this firmly," Mr Abbas said.
The interior ministry said the motive for the attack was not known but was being investigated.
Mr Salama is a chief aide to Palestinian Authority (PA) Interior Minister General Nasser Yousef.
Correspondents say that the attack is symptomatic of not only the power struggle in Fatah, but also the deteriorating security situation in the West Bank and Gaza where PA forces struggle to maintain control.
Earlier on Tuesday, two Israeli soldiers were lightly wounded when a roadside bomb exploded alongside their jeep in the Gaza Strip.
The bomb went as the soldiers patrolled the fence surrounding the main southern Jewish settlement bloc of Gush Katif, a military spokesman said.
There has been an increase in recent days of attacks by Palestinian militants on Israeli soldiers and settlers.