A French officer has died in a knife attack at the Paris police headquarters on Thursday, a police union official said.

According to the official, several officers were wounded in the midday attack. Another union official had earlier stated that two policemen had been injured, one gravely.

The assailant, an employee at the police headquarters, was shot dead.

The French media reported that the country’s interior minister was on way to the scene of the attack. The motive of the attack remains unclear.

Extremists have repeatedly targeted police in France in recent years. In 2017, a gunman opened fire on the Champs-Elysees boulevard, killing one officer before he was shot to death.

In 2016, an attack inspired by the Islamic State group killed a police officer and his companion, an administrator, at their home in front of their child.