Four more bodies have been found in the hidden burial ground that was discovered in El Salvador last month, bringing the total number to 28, the country's justice minister said Wednesday.

"There are already 28 (bodies) found" at the site on the El Limon ranch in Colon, a city 19 kilometers (about 12 miles) west of San Salvador, Ricardo Perdomo told a press conference.

The burial site includes more than 14 graves in an area of some 200 square meters (about 2,100 square feet), according to the Attorney General's Office, and investigators estimate that there could be as many as 44 bodies in all interred there.

Investigators began digging on the El Limon property on Nov. 19 and made the "first discoveries" three days later, the head of the organized crime unit in the AG's office, Rodolfo Delgado, said last week.

Militant members of the Pandilla 18 gang were behind the killings, the AG's office says.

Perdomo announced that "probably investigations will be begun in other places" around the country to determine if there are more clandestine burial sites.

Between January and Dec. 15, at least 2,391 people have been murdered in El Salvador, according to official figures.

But national police director Rigoberto Pleites said Wednesday that the force is "analyzing" the number of disappearances, which have almost doubled this year, since "possibly many of them may have been murdered."

Between January and Dec. 1, 1,070 people were reported missing, compared with 545 during the same period last year.

The increase has called into question the ostensible 52 percent reduction in murders due to a cease fire declared among gangs in March 2012. EFE