By Nick Parker, CNN
MEXICO CITY - Mexico City appeared to be immune from the drug cartel violence that has ravaged the rest of the country.
But the disappearance in May of 12 young people in the capital city shook that perception, and now a new grim discovery may raise fears even higher.
It was in a bar in central Mexico City where up to 12 young people disappeared in broad daylight on a Sunday morning in May.
Appeals from family members and candles have be laid at the door of the bar.
Now, attention in the case is focused on the grim discovery of a mass grave found at an eco park in a neighboring state.
Mexico City's attorney general said seven bodies have been found so far.
"At this stage, we will continue the excavation to verify the existence of more bodies. To reiterate, due to the conditions in which they are in, it is not possible to even identify the bodies we have found. This will be done by DNA tests," said Rodolfo Rios.
The disappearance of the group shocked Mexico City, taking place just off the famous avenue in an area known as a finance and tourism district.
Video footage released shortly after revealed a gang leading a number of the missing people away in cars.
One line of investigation has focused on a dispute between gangs operating in Tepito, an area of Mexico City known as a clearing house for contraband.
Results from DNA tests are expected over the weekend. For relatives of the missing, the agonizing wait must continue.