MEXICO CITY (AP) ― A Human Rights Watch report released Wednesday calls Mexico’s anti-drug offensive “disastrous” and cites 249 cases of disappearances, most of which show evidence of having been carried out by the military or law enforcement.

The report says the enforced disappearances follow a pattern in which security forces detain people without warrants at checkpoints, homes or workplaces, or in public.

When victims’ families ask about their relatives, security forces deny the detentions or instruct them to look for their loved ones at police stations or army bases.

Human Rights Watch criticizes former President Felipe Calderon for ignoring the problem, calling it “the most severe crisis of enforced disappearances in Latin America in decades.”

An email asking for comment and sent to Harvard’s Kennedy School of Government, where Calderon is a fellow, was not immediately answered Wednesday.

While the report acknowledges that current President Enrique Pena Nieto inherited the problem, it says he should act urgently “in cases where people have been taken against their will and their fate is still unknown.”

Mexico’s Interior Department, which oversees domestic security, declined to make an immediate comment about the report.

A civic organization released a data base late last year that it said contained official information on more than 20,000 people who had gone missing in Mexico over the previous six years.

In posting the date base on its website, Propuesta Civica, or Civic Proposal, said the information was collected by the federal Attorney General’s Office during Calderon’s recently ended administration.

The missing include police officers, bricklayers, housewives, lawyers, students, businessmen and more than 1,200 children under age 11.

They are listed one by one with such details as name, age, gender and the date and place where the person disappeared.

Among the examples cited by Human Rights Watch is evidence suggesting that marines detained about 20 people in three northern border states in June and July of 2011. Though it denied abducting the victims, the Navy later acknowledged it had contact with some before they disappeared.

In one such case, Jose Fortino Martinez Martinez was sleeping with his wife and four children at their home in the northern border town of Nuevo Laredo when he was woken by the sound of his door being knocked down.

That night in June 2011, eight masked men burst into his bedroom carrying automatic rifles and bulletproof vests with “Marina,” Navy in Spanish, written on them.

Martinez, 33, was taken away by those men, according to the several of his neighbors who testified at the time. Although Naval officials denied arresting him they said weeks later that they would investigate if marines were involved.

So far, nothing is known of Martinez’s whereabouts.

The report also says security personnel sometimes work with criminals, detaining victims and handing them over to the gangs. The report cites incidents in which investigators used information collected in a case to pose as kidnappers and demand ransom payments from the victims’ families.

Authorities frequently fail to take even the most basic investigative steps, such as tracing victims’ cellular phone or bank records, and often rely on investigations carried out by the victims’ relatives, the report adds.

Human Rights Watch recommends that the Mexican government take concrete steps to change security procedures, including issuing new rules that require that detainees be taken immediately to prosecutors’ offices and not be held at military bases or police stations.