Boston police Capt. Haseeb Hosein is the district commander at Area B-3 in Mattapan. He was off yesterday, Veterans Day, but he decided to work a detail near the intersection of Columbia Road and Stoughton Street.

When you’ve worked the streets of Roxbury, Dorchester and Mattapan as long as Haseeb Hosein has, you understand that a detail is actually front-line duty. And so it was yesterday, when a piece of life and death rolled his way around 12:30 p.m. on an MBTA bus.

Passengers who nervously bolted from the bus near the intersection of Columbia Road and Stoughton told Hosein about the guy standing in the rear, holding a hatchet to his neck and yelling that he was going to kill himself.

When he boarded the bus, Hosein saw a man he judged to be around 50. In a tone closer to a parish priest than a cop, Hosein calmly asked him, “What can we do to help? What do you need?”

Hosein noticed the man was clutching the hatchet close enough to his neck to break the skin. He told Hosein that he was a veteran, staying at the homeless shelter on Court Street downtown.

By the time the vet made that declaration, Haseeb Hosein was joined by BPD patrol officer David Godin, who uttered the words that may well have saved one troubled vet’s life.

“Sir, I want to thank you for your service,” Godin told him.

Hosein told colleagues later that David Godin essentially neutralized a very tense situation almost immediately with those words of gratitude and respect, the Boston Herald reports.