North Korea may be isolated and tightly controlled, but it apparently is no stranger to a problem that plagues capitalist countries: soccer violence.

A World Cup qualifying match between Iran and North Korea in the capital of Pyongyang erupted into a melee Wednesday evening when fans were enraged after referees failed to call a penalty against one of the visiting players.

Bottles and rocks were thrown on the field, and masses of North Koreans surrounded the Iranian team's bus after the match - a rarely seen display of public violence in the authoritarian country. North Korea lost, 2-0.

The North, which in February claimed to have built nuclear weapons, has recently gone out of its way to express its friendship to Iran - whose nuclear program has drawn strong international concern that Tehran also secretly hopes to build atomic bombs. Both countries were part of President Bush's "axis of evil," along with Saddam Hussein-era Iraq.

None of that brotherhood was evident after the loss at Kim Il Sung Stadium.

As North Korea's Nam Seong Chol charged toward the Iranian goal, he fell down - apparently pulled by an Iranian defender.

When the referee did not award North Korea a penalty kick, nearly the entire team charged the official, and some reports said fans began ripping up their seats and tossing them on the field.

Photos from inside the stadium showed police in dark green uniforms restraining some people in the crowd.

"The atmosphere on the pitch and outside the pitch was not a sports atmosphere," Iran coach Branko Ivankovic said after the match, according to the Web site footballasia.com. "In sport, you win and you lose, but it is very disappointing when you feel your life is not safe."

After the match, the Iranians had to take shelter inside the stadium before making their way to their team bus.

Due to the violence, Japanese government officials on Thursday urged North Korea to ensure adequate security when its team travels there in June for another World Cup qualifier.

Chief Cabinet Secretary Hiroyuki Hosoda said Japanese soccer officials might meet with international soccer officials to discuss the issue before the June 8 match.

Longtime rivals Japan and North Korea have no diplomatic relations, and have been locked in a dispute over the North's kidnapping of Japanese nationals in the 1970s and '80s.

"Many Japanese fans may travel to Pyongyang for the game. We want North Korea to take steps for their safety and that of the players," the government's top spokesman said at a news conference. "Players should be able to play safely and fans should be protected at international matches."

Japan Football Association deputy chairman, Junji Ogura, criticized North Korean authorities' handling of security and said he wants Asian Football Confederation officials at Japan's match in Pyongyang to make sure it goes smoothly.

"I don't think the security force there was doing its job of protection," Ogura said, adding: "And it's not right that the players reacted the way they did to the referee's call. One of the things we asked (North Korea) to do was to respond to that."

(Agencies)