Authorities in northern Mexico still have no leads after searching two days for 20 people with a Colombian-style band who went missing after a private performance at a bar, an official with the Nuevo Leon State Investigation Agency said Sunday.

The 20 people include 15 members of Kombo Kolombia and the band's crew.

People living near the bar in Hidalgo municipality north of Monterrey reported hearing gunshots about 4 a.m. Friday, following by the sound of vehicles speeding away, said the source with the state agency. He spoke on condition of anonymity because he was not authorized to be quoted by the news media.

The officials added that gunfire is common in the area, and said investigators found spent bullets nearby.

Relatives filed an official report about their missing loved ones on Friday, after they lost cellular telephone contact with them following the Thursday night performance. When family members went to the bar to investigate, they found the band members' vehicles still parked outside.

For three years, Kombo Kolombia has played a Colombian style of music known as vallenato, which is popular in Nuevo Leon state. Most of the group's musicians were from the area, and have held large concerts in addition to bar performances.

Nuevo Leon state officials said one of those missing is a Colombian citizen with Mexican residency.

Members of other musical bands, usually groups that performed "narcocorridos" celebrating the exploits of drug traffickers, have been killed in Mexico in recent years. But Kombo Kolombia did not play that type of music and its lyrics did not deal with violence or drug trafficking.