Police have released a sketch of one of the thieves who pulled off a brazen robbery in Merrimac earlier this week. Police say a three men robbed a Woodland Street home early Wednesday. Authorities allege the trio forced a female resident, who ran a business out of her home, to open her safe and give them money. The three suspects, according to Merrimac Police, made off with a “large sum of cash.” Police did not say how much, however. The victim described all three as white men in their 20s or early 30s. Two of the three were wearing hooded sweatshirts. Police said the suspects were not known to the victim, who did not suffer any serious injuries. Massachusetts State Police assisted in the search for the subjects, which thus far has been fruitless.