MARYLAND: Two people were killed and 28 others were injured in a mass shooting in Baltimore, Maryland, early Sunday morning, at the scene of a holiday weekend block party, according to police and local media reports.

An 18-year-old woman and 20-year-old man were killed and three victims were still in critical condition, according to police in Baltimore, a city about 40 miles (64 km) north of Washington, D.C.

The suspect or suspects were still at large.

“This investigation is ongoing, and we will not rest until the people responsible are held accountable,” Mayor Brandon Scott and the police department said in a joint statement.

The tragedy rattled the city at the start of the Fourth of July holiday weekend, when Americans typically gather for parades, barbecues and fireworks. The shooting occurred shortly after midnight at the “Brooklyn Day” block party in the Brooklyn Homes neighborhood of Baltimore, which hundreds of people attended, local media reported.

A witness told TV station Fox 45 that they had heard 20 to 30 shots fired.