BOSTON — The Massachusetts Port Authority has asked to be released from the last pending wrongful death lawsuit related to the Sept. 11, 2001 terrorist attacks.

The suit filed by the mother of a Boston man who died in the attacks says hijackers were able to board United Airlines Flight 175 in Boston because of negligence by United and Massport, which runs Logan International Airport.

The Boston Globe reports that Massport in a filing last week said the airport had no role in screening passengers and no “causal connection” to the attacks.

The suit was filed in federal court in New York City by Mary Bavis. Her son, Mark, died when his plane crashed into the World Trade Center’s south tower.

A Massport spokesman had no comment. Bavis’ lawyer could not be reached.