The Dutch police siege of a building in a residential area of The Hague this evening appeared to be over after two young men gave themselves up to police.
A police spokesman said a special police unit had raided the apartment in the Dutch capital following a 14-hour standoff after three officers were injured before dawn when suspects they were trying to arrest threw a hand grenade.
"The police is now investigating the apartment," the spokesman said. "The siege is over."
Earlier air space over The Hague was closed as the standoff continued. Officials declined to say whether the operation was linked to the murder last week of a filmmaker by a suspected Islamist extremist.
"On the request of criminal investigation branch, an arrest team this morning at 2.45 tried to arrest suspects in an ongoing probe by the crime squad into terrorism," chief justice official Mr Han Moraal told a news conference.
Mr Moraal said three police officers were injured when a hand grenade was thrown at them. Shots were also fired, he said. Two of the injured officers were in hospital while one had been allowed to go home, police said.
Dutch police have arrested 10 people in their investigation into the killing of film director Theo van Gogh last week and are still holding six, including the prime suspect Mohammed B., who has been charged with murder and suspected links to a terrorist group.
Mr Van Gogh enraged Muslims with his criticism of Islam, in particular a recent film which said Islam promoted violence against women and showed Koranic verses written on a woman's naked body. He was cremated on Tuesday evening.
The Netherlands has seen a series of apparent tit-for-tat attacks since Mr Van Gogh's murder, including an arson attack on a Muslim school last night, where the words "Theo R.I.P." were scrawled on the walls along with a "White Power" sign.
A little-known Islamist group threatened yesterday to hit the Netherlands if the attacks on Muslim buildings did not stop. The country has received several threats from Islamic militants over the presence of 1,300 of its troops in Iraq.
Officials said the airspace over The Hague had been closed today amid the ongoing operation. They sealed off the area after the explosion and an anti-terrorism unit was on the scene. It was not clear if anyone had been arrested.