Police in Iowa are investigating the scene of a nightclub shooting that killed two people and injured 10 others.

Shots broke out Sunday at the Taboo Nightclub and Lounge on Third Street in downtown Cedar Rapids just before 1:30 a.m., according to the Cedar Rapids Police Department.

Cedar Rapids police officers were on routine downtown patrol when the shooting occurred and “were able to respond immediately,” according to the police department.

The two victims were pronounced dead at the scene, while the 10 injured were treated at area hospitals, police said. Their conditions were not released by police.

It is unclear what led to the shooting. Police did not release information on whether the gunman was in custody but announced around 6 a.m. that the scene was secure and there was no threat to public safety.

Investigators are asking that anyone present at the time contact the police department.

ABC News’ Keith Harden contributed to this report.