LAWRENCE, Mass. — The field of candidates hoping to succeed Democratic congresswoman Niki Tsongas is growing.

State Rep. Juana Matias, a Lawrence Democrat, announced Thursday she was entering the race for Massachusetts’ third congressional district seat.

In a statement, Matias said she came to the United States from the Dominican Republic with her family at the age of 5. She pledged to fight for working families in Congress.

Tsongas is retiring from the House after five terms. Other Democrats eyeing the seat include state Sen. Barbara L’Italien of Andover and Daniel Koh, the former chief of staff to Boston Mayor Marty Walsh, who is a native of Andover.

Republican Rick Green, a businessman from Pepperell and former chairman of the Massachusetts Fiscal Alliance, officially announced his candidacy earlier this week.