A police inspector has been arrested in Haiti's capital on suspicion of involvement in a deadly gun attack on anti-Aristide demonstrators this month.

PORT-AU-PRINCE -- (AP) -- Authorities have detained a senior police officer suspected in an armed attack on protesters that killed seven people, including a Spanish journalist, a human rights group said Monday.

Police Inspector Jean Michel Gaspard was held on Sunday in Port-au-Prince, but no charges have been filed, pending an investigation, Pierre Esperance, director of the Coalition for Haitian Rights, told The Associated Press.

Police could not immediately be reached for comment.

Authorities believe Gaspard took part in the March 7 shooting attack on thousands of protesters demanding the prosecution of ousted President Jean-Bertrand Aristide, Esperance said.

Among seven people killed was television correspondent Ricardo Ortega of Spain's Antena 3 network.

Ortega, 37, was shot in the stomach. Photographer Michael Laughlin, 37, of the Sun-Sentinel newspaper in Fort Lauderdale, was shot in the shoulder and face. Both were taken to a hospital, where Ortega died.

Witnesses blamed Aristide supporters for the shooting, but foreign peacekeepers who said they killed one gunman could not confirm who was responsible.

Gaspard's detention comes a week after police held reputed Aristide militant Yvon Antoine for alleged involvement in the same attack, as well as an assault on the dean of Haiti's State University on Dec. 5.

Gaspard worked at the same police station as five other officers detained last week on suspicion of killing five Aristide supporters.

No charges have been filed in either case, Esperance said.

Ortega began his career in Moscow and worked for Antena 3 from 1994. He covered the Sept. 11 terror attacks and the wars in Iraq and Afghanistan as well as the Chechnya conflict.

Meanwhile, in Cap Haitien, angry civilians protested Monday's rebel hand-over of two police stations to officers accused of abuses, underscoring difficulties facing a U.S.-led interim government that has praised the rebels as liberators but also says all factions in Haiti must disarm.

''If the police try to get rid of the rebels, we will attack the police and take back the stations,'' threatened Joabilien Saint-Fidor, a 36-year-old among about 100 people shouting ``Down with the police!''

The hand-overs came as rebel commander Louis-Jodel Chamblain discussed surrendering power to police in Cap Haitien, Haiti's second largest city, with 500,000 people, and other northern strongholds.

Even as those talks continued, Chamblain indicated the superior power of the rebels -- who outgun and outnumber Haiti's demoralized police force -- vowing to kill Aristide if he returns from exile.

Chamblain's fighters still control much of northern Haiti, manning police stations they torched during the rebellion and patrolling with weapons through the same cities as French troops.

A small contingent of Haitian police officers who fled before the popular rebellion that erupted Feb. 5 have returned, but they lack weapons, which were looted during the fighting, the trust of the people, and a clear mandate from the interim government of Prime Minister Gerard Latortue.