Relatives of people missing in Mexico blasted authorities Wednesday as seemingly more interested in manipulating the data on the disappeared than on conducting thorough investigations.

The government last week revised the number of people believed to have disappeared since Mexico launched a war against drug traffickers in 2006, reporting that 22,322 had been reported missing. That was significantly higher than earlier estimates. In May, the government had said 8,000 people were missing.

Speaking to reporters, parents of those missing and representatives of civil organizations criticized the government's reports as confusing and their actions as insensitive.

Researcher Ximena Antillon said authorities have failed to say what methodology they are using to come up with their figures.

Maria Guadalupe Fernandez Martinez, 64, whose son disappeared in 2009 in the northern border state of Coahuila, said a government official recently called her to ask whether she had yet found her son.

"Why call our home when he is still missing?" Fernandez asked. The official, she said, spoke "without showing a hint of sensitivity, as if it were a little animal that disappeared."

The Interior Department, which is in charge of security in the country and has released the figures on missing people, did not immediately respond Wednesday to a request for comment.

It is unclear how many of the missing may have been kidnapped or killed by drug gangs, which frequently bury their victims in clandestine graves.

The National Citizens Observatory said Tuesday its analysis of kidnappings in the last two decades shows that kidnappers increasingly are targeting working class people, many times demanding ransoms of $50 or less.

"We are seeing a large number of makeshift gangs," said Francisco Rivas, director of the non-governmental group. "Unfortunately, kidnapping is one of the crimes that has become more democratic."

Rivas said his organization has heard of cases in which kidnappers have captured bricklayers and janitors and demanded ransoms of 500 pesos, about $38.

Government officials have estimated that the vast majority of kidnappings — more than 90 percent — are never reported. Official numbers show there were 1,698 kidnappings reported in 2013, a 20 percent increase compared to the previous year. But they acknowledge the actual number was probably more than 100,000.