A lawyer for a Long Island man accused of fatally shooting his wife says the 65-year-old man has been suffering from dementia for years.

Robert Brown was arraigned Wednesday on murder charges in the death of 71-year-old Sarah Brown, whose body was discovered in their Riverhead home on Tuesday after an hours-long standoff with police.

Suffolk County police say officers had responded to a report of a man carrying a handgun Tuesday morning when they found Robert Brown barricaded in the house. He was taken into custody after police knocked down the door about five hours later.

Newsday reports that Brown is being held without bail. His lawyer says he's a lifelong resident of Riverhead and has no criminal record.