Jennifer Lopez is at the centre of an investigation after a dog allegedly escaped from her home and attacked a neighbour.

The boxer, which is believed to be owned by the singer/actress' ex-boyfriend Casper Smart, is believed to have broken free from Lopez's mansion in California in December (14) and bitten a local resident on the hand and arm.

Officials at Animal Control launched a probe into the incident, and slapped Smart with a citation for an unleashed dog, according to Tmz.com. The pet is said to have been quarantined at Smart's home while officials look into whether the dog poses a danger.