A letter shows a former police officer who killed his former daughter-in-law and another woman at a Delaware courthouse before fatally shooting himself was diagnosed more than two decades ago with a brain tumor.

A neurosurgeon in Philadelphia who examined Thomas Matusiewicz (muh-TOO'-suh-wits) in 1990 diagnosed a tumor called a meningioma.

In the letter to another doctor obtained Wednesday by The Associated Press, the neurosurgeon said Matusiewicz suffered no symptoms and recommended only that the tumor be monitored to see if it was growing, in which case surgery was recommended.

Police say Matusiewicz shot and killed the two women last week at the New Castle County Courthouse before trading fire with police and killing himself. His family has said his actions may have been affected by an untreated brain tumor.