A Dominican Republic man has been charged with stealing a U.S. citizen's identity 40 years ago and tricking officials into giving him their social security number so he could live and work in America.

The man, whose true identity remains unknown, was convicted in Boston on Thursday of aggravated identity theft, using a passport obtained through false statements, stealing public funds and misuse of a social security number.

He could face up to 17 years in prison when he is sentenced on September 18.

Federal authorities say the man obtained the birth certificate of a U.S. citizen from Puerto Rico some time around 1975.

At that point, he didn't have the U.S. citizen's social security number so he obtained a fake card bearing the man's name and another number assigned to a different person from Puerto Rico.

A Dominican Republic man has been accused of stealing a U.S. citizen's identity to obtain work in America, travel on a passport and obtain unemployment and housing benefits

He went on to use the fake social security card from 1975 to 1994 to obtain work in New York and then Boston.

Authorities said the man was notified in 1994 by the IRS that the name on his social security card didn't match the number that he was using. He was told to go to a local social security administration office to resolve the issue.

The man took the letter to an office in Roxbury, Massachusetts where he convinced the employee that he was the person whose identity he had stolen and that he had forgotten his real social security number.

He provided the name, date of birth, place of birth, and parents’ names on the U.S. citizen’s birth certificate.

The employee entered the information he provided into the system and a match came up for the U.S. citizen's real social security number.

The man was then able to obtain a real copy of the social security card bearing the U.S. citizen's name and number.

Authorities say he went on to use the social security card for the next 18 years until the U.S. citizen died in Puerto Rico in 2012.

A fraud investigation was launched when authorities realized the dead person's social security number was being used in Massachusetts.

The man is accused of using the stolen identity to work in Boston, obtain and travel on a U.S. passport, apply for unemployment benefits and obtain public housing benefits for himself and his family.

He is due to be sentenced on September 18.