'Shutter Island' slashes new releases Friday

'Shutter Island' holds on to No. 1 for now...

Martin Scorsese's "Shutter Island" defended the No. 1 spot at the North American box office Friday with a solid $6.6 million in ticket sales, according to early studio estimates. Ever since its release last weekend, "Island" has reached a cumulative gross of $59.5 million.

New entry "Cop Out," the new comedy directed by Kevin Smith, finished second Friday, earning $5.975 million. The film, which is now playing at 3,150 locations, stars Bruce Willis and Tracy Morgan as two buddy cops trying to find a stolen baseball card. Read my review here.

Following closely in third place was Breck Eisner's horror remake "The Crazies," which bagged $5.970 million from ticket sales at 2,476 locations. The film follows a group of people trying to stay alive while everyone else in their small town goes crazy and turns to brutal violence.

Meanwhile, James Cameron's "Avatar" landed in fourth place with $3.1 million, reaching a domestic total of $696 million after a superb 71-day run. "Valentine's Day" followed at No. 5, generating $2.9 million for a total haul of $93.7 million.