CONCORD — Someone left two racist notes taped to the door of a family of Bhutanese refugees, the third such incident targeting immigrants in the city over the past two years.

Police said the notes were left Sunday and Monday at an Eastside Drive apartment building at the Regency Hill complex in the Concord Heights section of the city. One note was written in marker, while the other was inked in pen.

The notes called the family of Bhakta Gurung, his wife, Bishnu, and their two children “inconsiderate (expletive)” who receive everything for free, according to police.

No one in the family, which settled in Concord four months ago, reads English. The Gurungs came from a Nepalese refugee camp after being exiled from their native Bhutan.

A Lutheran Social Services case worker visiting the family Wednesday contacted police.

Lt. Timothy O’Malley said a detective assigned to the previous cases that happened in August 2011 and September 2012 in the city’s South End is investigating the latest incident.

Police, however, are not certain a crime was committed.

O’Malley said investigators are looking into whether a harassment charge could be brought but, he said, everyone is entitled to free speech, no matter how abhorrent or reprehensible it may be.

He said that in the South End incidents an individual scrawled hate messages on the side of apartment buildings using a marker. If caught, the individual would be charged with criminal mischief for causing damage to the building with an enhanced penalty for hate language.

Still, he said, investigators want to find the individual who left the notes at the Gurungs’ home. The concern, O’Malley said, is that it could escalate into something else.

“We certainly would want to find the individual who wrote them and talk to that individual about them,” he said.

Investigators believe the South End cases are linked and the work of the same individual, and are “99.9 percent” certain someone else is responsible for the notes left on the Gurungs’ door, according to O’Malley.

He said there are clear differences between the incidents: In the Concord Heights case, the insults were written on paper, not scrawled on the side of a building; they targeted the Bhutanese family, and the handwriting is not the same.