Union members Thursday morning began returning to work at a Hannaford distribution center in South Portland after a 24-hour strike.

The short strike by more than 200 members of United Food and Commercial Workers Local 1445 was launched early Wednesday morning, two days after Delhaize America Distribution, the company that operates the distribution center, said it had understood there would be no strike before a scheduled mediation next Monday. The company is a subsidiary of Ahold Delhaize, an international supermarket conglomerate that also owns Hannaford.

Union officials denied there had been any agreement to wait until Monday to strike.

Union workers in South Portland are tired of being disrespected by company owners and have become a “militant” unit, union president Jeff Bollen said Wednesday. On Saturday, they voted overwhelmingly to reject the company’s final contract offer and authorize a strike. Union negotiators said the proposed contract would have slashed wages for new workers and did not address soaring health insurance costs.

In an email Wednesday morning, Delhaize America Distributors spokeswoman Christy Phillips-Brown said the company was “disappointed” that the union decided to strike after agreeing to a mediation date.

The strike didn’t seem to have an immediate effect on Hannaford stores. The distribution center services 103 Hannaford stores in New England, including 63 in Maine.

UFCW Local 1445, based in Dedham, Massachusetts, represents 15,000 workers in Maine, Massachusetts and New Hampshire, including 246 employees at the Hannaford warehouse.

Gillian Graham can be contacted at 791-6315 or at:

ggraham@pressherald.com

Twitter: grahamgillian