National Police spokesman Hector Ivan Mejia declined to comment on the videotape of the shootings because he said they are under investigation. He also said he knew nothing about Carranza's case, though he noted that Honduras is in the grip of gang warfare, marked by groups of assassins acting on behalf of organized crime.
"We've detected a group of people carrying out these types of operations and we're working to resolve them," Mejia said. "I have no information indicating the state is acting in this manner. If police were involved in these types of crimes, they would be detained. Authorities cannot and should not combat crime in this manner."
As far back as 1988, the Inter-American Court on Human Rights condemned Honduras for failing to document the fate of detainees and for allowing police to obstruct judges investigating cases, "including threatening them and denying the disappearances."
Bonilla was appointed police chief last May after his predecessor, Gen. Ricardo Ramirez del Cid, was ousted amid charges that police were involved in the kidnapping and the killing of one of Honduras' best-known journalists, Alfredo Villatoro.
Less than a year later Ramirez's own son was killed. Ramirez called Bonilla the prime suspect in the Feb. 17 assassination of Ramirez's 17-year-old son, Oscar, killed in a shootout between his bodyguards and 10 hooded gunmen who entered a restaurant where they were eating.
Ramirez said Bonilla was nearby when it happened, though Bonilla has denied any involvement. President Porfirio Lobo has called Ramirez's comments imprudent.
Honduras made a failed attempt to purge its National Police of corrupt officers after some were implicated in the 2011 murder of the son of Julieta Castellanos, rector of the National Autonomous University of Honduras.
Between May and November, hundreds of police officers underwent background checks and polygraphs. By the end of the year, 33 of them were removed, but the Constitutional Court stopped the purge, ruling that it violated officers' rights.
One problem in Honduras is that the prosecuting arm of government, the Public Ministry, relies on the criminal investigations department to investigate crimes. But the members of that agency are police officers, which means in the case of death squads, police would be investigating themselves.
The Honduran police force "appears to be an institution that is absolutely beyond reform," said Victor Meza, president of the Commission to Reform Public Security.
Critics say the Carranza case is evidence of that.
Carranza and his girlfriend had only lived in the modest complex a month when they disappeared.
A neighbor agreed to tell the AP what happened the night of Jan. 9 on condition that his identity would not be made public. The neighbor said he heard noises around 9:30 or 10 p.m.
"They shouted that they were police. There were several, judging from the footprints they left in the flowers. They opened the gate, there was noise for a few minutes, like kicking, and then they left," he said. Neighbors said someone must have let them through the locked gate.
Gang lookouts alerted a fellow 18th Street gang member, who calls himself Jonathan Flores, a driver for Carranza. Flores said he was the first to arrive after the couple was taken. The door to Carranza's house was left open.
"The house was ransacked and the dog was alone," Flores said. "The neighbors told me it was quick, with no shouts or shots fired."
As he left he saw two Nissan SUVs without license plates, and six or seven masked men in civilian clothes with bullet-proof vests and large guns chatting with the neighbors. Carranza's mother said they came back to rob the house, taking a 50-inch plasma television, a home theater screen and speakers, cellphones, Carranza's collection of tennis shoes and about $500 in cash that gang members typically have on hand.
Flores said the police are the only explanation for Carranza's disappearance. He and others would know if Carranza had been taken by a rival gang.
"Look at the detention photo," he said. It shows the feet of the people surrounding the prone suspect. "A gang member doesn't work in officials' shoes."
Nor does Flores believe that Carranza fled.
"He didn't have a motive. Things were working well here," Flores said. "And he would have told his mom."
His mother, Alvarado, filed a complaint with the prosecutor's Office on Human Rights, using the newspaper photo as proof. The unidentified official close to the investigation said the duct tape over the face and marks on the body, including what appears to be a dislocated elbow, would constitute torture.
The human rights prosecutor waited the 48 hours required by law and visited the morgue in an unsuccessful search for a corpse. After that, he made a habeas corpus request with the Supreme Court. The law requires verification of a detention within 24 hours if the person hasn't appeared before a prosecutor or a judge, the official said.
The Supreme Court has yet to respond. But the official close to the investigation says police acknowledged the day after the disappearance that there was a detention order for Carranza and said he would be processed quickly. Police later denied any knowledge about Carranza.
"A police officer cannot do this on his own," the official said. "You need a network of information and collaboration to carry out the arrest and disappearance of people."
Associated Press writers Luis Alonso Lugo in Washington and Katherine Corcoran in Mexico City contributed to this report.