He bit off all he could chew.
An unhinged man who chomped off a piece of a cop’s middle finger at a Brooklyn stationhouse swallowed the digit before cops could retrieve it, authorities said.
Ainsley Johnson, 34, gulped down the fingertip during a fight with a cop who was escorting him into a jail cell at the 69th Precinct in Canarsie about 6 p.m. Friday, cops said.
About an hour earlier, cops arrested Johnson on E. 99th St. after he wigged out on a 46-year-old resident, breaking the windows of the man’s 2003 BMW and crushing his victim’s mailbox with a cement planter.
Cops took Ainsley in on criminal mischief charges.
While at the precinct, Johnson resisted as a 24-year-old cop who tried to re-handcuff him — and the two tusseled, falling onto the floor.
That’s when things turned feral.
Ainsley bit off the cop’s finger “from nail to tip,” police sources said.
Medics rushed the two-and-a-half-year veteran to Kings County Hospital.
Ainsley was also injured in the fight and was taken to Brookdale University Hospital and Medical Center for treatment. The extent of his injuries weren’t disclosed.