Updated

The nation's second-largest commuter rail line says it has completed most of its priorities to improve safety following a series of accidents last year.

The Metro-North Railroad says in a 100-day action plan released Wednesday it has established an investigation unit to look into the causes of accidents, overhauled a system safety plan and improved employee training programs.

Metro-North serves Connecticut and New York. It says it still must install alerter devices designed to ensure engineers remain responsive.

The Federal Railroad Administration responded to a December derailment that killed four passengers. It said in March that Metro-North allowed safety to erode while pushing to keep trains on time.

Connecticut Gov. Dannel P. Malloy says the report has taken longer than he wanted but Metro-North is making itself safer.