Seven confirmed cases of E. coli O157:H7 amongst children are being investigated in Amarillo, Texas.

Dr. Roger Smalligan, the public health authority for Potter and Randall counties, said four children, most under the age of 5, have been hospitalized. Smalligan said officials are trying to determine how and where the children might have contracted the bacterial infection.

Smalligan said six of the seven children had some contact but couldn’t discuss what that contact was or if the bacteria was showing up in a certain part of town or at a certain location. He did say that several of the children were related to each other.