Four people were taken to hospitals Tuesday after officials said they suffered apparent overdoses of synthetic marijuana.

Tim Wilson, a spokesman for the D.C. fire department, said that the cases are similar to those on June 5, when seven people were given emergency medical treatment after apparently using the drug.

The call came shortly before 3 p.m. at the Community for Creative Nonviolence in the 400 block of Second Street NW, near Judiciary Square. The conditions of the patients were not immediately known. He said that they were found either in the shelter, the District’s largest homeless facility, or just outside.

On June 5, Wilson said it seemed that the seven patients had used the same drug and appeared lethargic, unresponsive or incoherent. Several were found in the area around the shelter, which has 1,350 beds.

On Monday, Mayor Muriel E. Bowser (D), joined law enforcement and health officials and vowed to target suppliers of synthetic drugs after a spike in overdoses in the past month. She said she would introduce emergency legislation to give the D.C. police the authority to shut down any business found selling the drugs for a period of 96 hours while police investigate.

In addition, D.C. Police Chief Cathy L. Lanier announced changes in how detectives plan to target illegal drugs in the District, focusing on suppliers who use the Internet or stores to sell synthetic versions of drugs.