Updated

The owner of a Boston company facing manslaughter charges stemming from the deaths of two employees in a trench collapse has pleaded not guilty and been released.

Kevin Otto and an attorney for Atlantic Drain Services Inc. entered not guilty pleas at Thursday's arraignment.

Authorities say Robert Higgins and Kelvin Mattocks died when the 14-foot-deep trench they were working in last October caved in and then filled with water.

Prosecutors say the company failed to strengthen the trench walls as required by federal regulations.

Otto also is accused of providing falsified records to the Occupational Safety and Health Administration.

Otto's lawyer said in court he intends to "fight this case." He had no comment outside court.

A company lawyer says Otto is "very upset."