PHILADELPHIA (AP) — Authorities say more charges are likely in the case of a Philadelphia man accused of barricading himself inside a house and shooting six police officers during a long standoff last week.

But District Attorney Larry Krasner also warned Monday that the investigation into the "factually complicated case" could take months because of the amount of evidence that must be reviewed.

Thirty-six-year-old Maurice Hill is charged with attempted murder, assault and other counts.

He is accused of shooting at officers who were serving a drug warrant Wednesday and then keeping police at bay while he fired from inside a building.

Hill's attorney has not responded to a message seeking comment.

The six officers were released after being treated at hospitals. Four other men are charged with drug offenses.

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