Nova Scotia's police watchdog has launched an investigation into an allegation police deleted a bystander's video after the arrest of a 17-year-old youth last year.

The Serious Incident Response Team says a complaint was filed in November by the youth's legal counsel.

According to SIRT, on June 15, 2015, three members of the Halifax Regional Police arrested the man at the Reigh Allen Centre, where the man was a resident. 

After the arrest, one of the officers allegedly deleted a phone video recorded by a third party of the incident.

SIRT says the potential obstruction of justice meets their mandate to investigate matters of significant public interest.