The offices of the Beitar Jerusalem soccer team were set on fire early Friday in an apparent arson attack, police said, a day after four of the club's fans were charged with anti-Muslim chanting at a recent game.

The attack also followed an announcement by police that it would begin deploying undercover units and beefing up police presence at games to track down those fans involved in racist chants.

Police spokesman Micky Rosenfeld said Friday's attack left extensive damage to the team's administrative offices next to its training field. The office walls were charred, and team trophies and soccer cleats were scattered about. No one was hurt in the attack, and the police were searching for suspects.

Rosenfeld pledged the police would use "every legal means in order to prevent the continual racism, which is basically destroying the club."

In a statement to reporters, Jerusalem mayor Nir Barkat said those responsible for the attack were "not fans but criminals."

Beitar Jerusalem is known to have fans hostile to Muslims and Arabs and in the past fans have been punished on occasion for chanting anti-Muslim slurs at games.

Tensions have been bubbling ever since the team announced last month it would sign on two Muslim Chechen players — Zaur Sadayev and Gabriel Kadiev — in a break from the team's unofficial tradition of not signing Arabs or Muslims.

At a league game in January, spectators protesting the decision unfurled large banners with anti-Muslim undertones, drawing harsh rebuke from Israel's president, Jerusalem's mayor and other officials. On Thursday, four fans were indicted for the behavior.

Last week, hundreds of police patrolled a game between Beitar Jerusalem and a team from the Arab town of Umm al-Fahm. No major incidents were reported, and 12 fans from both sides were banned from the game.

Police are planning heavy deployment next week when Beitar plays another team from an Arab town.

Later Friday, Prime Minister Benjamin Netanyahu condemned the fans' behavior and opposition to the Chechen players.

"This behavior is shameful," Netanyahu said in a statement to reporters. "We cannot accept such racist behavior. The Jewish people, who suffered excommunications and expulsions, need to represent a light unto the nations."