SEASIDE PARK, N.J. (AP) - Three police officers are being treated for injuries they received falling out of the back of a pickup truck after spending all night doing security patrols while firefighters worked on a massive blaze on a Jersey shore boardwalk.

Gov. Chris Christie says he does not know the condition of the Seaside Park police, but said two of them fell on their heads.

Thursday's fire leveled four blocks and about 30 businesses in Seaside Park and neighboring Seaside Heights, communities badly damaged last year during Superstorm Sandy.

The cause of the fire is under investigation.