Embattled Massachusetts Department of Children and Families Commissioner Olga Roche has resigned under mounting pressure following the deaths of three children.

Interim Commish Erin Deveney brings "management experience at a large organization." -Deval Patrick #mapoli

The move Tuesday comes after calls from top Democratic lawmakers — including Massachusetts House Speaker Robert DeLeo and Senate President Therese Murray — for Roche to be replaced as head of the child welfare agency.

Authorities say the family of a 2-week old Fitchburg baby who died over the weekend was being monitored by state child welfare officials.

In the second case, a DCF spokeswoman says a fax from Grafton police about possible harm to a 4-week-old who later died was misplaced for six days.

The body of a third child, 5-year-old Jeremiah Oliver of Fitchburg, was found off a highway this month. Jeremiah's family was also under DCF supervision.