Two Salem police detectives stood by this week and watched as surgeons at North Shore Medical Center Salem Hospital pulled 27 bags of heroin from the stomach and intestines of a man who had checked in with symptoms of an overdose, officials said.

Medical staff at the hospital allegedly recovered just over 163 grams of the suspected drug Tuesday from the body of Miguel Rodriguez, 51, of Lynn, who police say had just returned from the Dominican Republic.

He faces drug-trafficking charges.

Salem police Captain Conrad Prosniewski said Rodriguez became ill while having dinner in Lynn. Hospital staff called police after they examined his stomach and detected foreign objects, Prosniewski said.

Rodriguez was treated with the overdose-reversing drug Narcan and quickly went into surgery as two investigators looked on.

“They were actually outside of the room, viewing as the doctor was removing them and putting them into a tray,’’ Prosniewski said.

The drugs have a street value of more than $16,000, police said.

Police believe one of the bags had broken in Rodriguez’s stomach, leading to the overdose.

He was arraigned in the hospital Thursday and pleaded not guilty. A judge set Rodriguez’s bail at $500,000 and ordered him to surrender his passport.

The incident comes as Salem and other North Shore communities face a recent spike in heroin overdoses. The city has seen 29 overdoses this year, 15 of them in March. So far, three people have died in Salem in 2015.

Prosniewski said he believes the March increase has been caused by especially dangerous drugs that have been circulating — probably containing the additive fentanyl, which increases potency and risk.

Last weekend, Prosniewski said, two twin sisters overdosed, and one had to be treated 10 times with Narcan.

“That was a close call,’’ he said.

But the treatment does not always work.

On one occasion, authorities treated an overdose victim with Narcan six times before he died, he said.

“It’s terrific, but it isn’t a cure,’’ he said.

Andy Rosen can be reached at andrew.rosen@globe.com. Follow him on Twitter at @andyrosen.