Police are searching for the man behind a string of knifepoint robberies across Long Island, and struck again twice this holiday weekend.

The first incident happened Saturday night at the Subway on Jerusalem Avenue in North Merrick.

Police say an employee fought him off with a sandwich tray and hit a panic alarm.

According to police, two hours later a masked man hit a TCBY yogurt shop on Sunrise Highway in Lynbrook, getting away with some cash.

Police say the incidents fit the pattern of a masked robber targeting mainly ice cream, sandwich and coffee shops on Long Island.

These last two robberies bring the total to 14.

Nassau and Suffolk Police have increased patrols near businesses like the ones held up.