The US government has filed a $100m (£75.6m) lawsuit against the owner and operator of a cargo ship that crashed into and destroyed a Baltimore bridge.

Justice Department officials said the companies, Synergy and Grace Ocean, were "well aware" of the issues with the Dali before it lost power and crashed into the Francis Scott Key bridge on 26 March, leading to the deaths of six people.

The government said it cost more than $100m to clear the estimated 3,000 to 4,000 tonnes of debris caused by the crash and enable the Port of Baltimore to reopen.

Attorney General Merrick Garland said he wanted to ensure that the costs were "borne by the companies that caused the crash, not by the American taxpayer".

The Justice Department said any money recovered would go towards the costs of reconstruction.

The bodies of six workers killed as they repaired pot holes during a nightshift were recovered from the Patapsco river in the days after the disaster. The families of three said on Monday they were suing Grace Ocean.

The Justice Department's lawsuit, filed in district court in Maryland, alleges that the ship's electrical and mechanical systems were improperly maintained and that the crash was "entirely avoidable".

A preliminary National Transportation Safety Board report found that the Dali had lost electrical power four times in less than 12 hours before colliding with the bridge.

The damage took months to repair and stalled commercial shipping into the port, one of the busiest in the US.

Twenty members of the Dali's crew were stuck on the ship for weeks as it remained entangled by tonnes of concrete and steel from the wreck.

The disaster is considered the most expensive marine casualty case in US history.

Grace Ocean filed a motion earlier this year in a federal court to limit its legal liability.