Chelsea police arrived at a Congress Avenue home last month to find exactly what a caller had described: a bloodbath. A man in his 20s had cut his wrists, slashed his neck, and, with officers inside the second-floor apartment, stood with the knife still in his hand.

“I have to finish this!’’ he yelled as he brought the knife to his throat, according to an internal police report.

That began a tense albeit brief showdown with officers, who repeatedly ordered him to drop the weapon. For a moment, he did, before suddenly tensing and bringing the knife back to his neck. It prompted an officer to fire his department-issued Taser, striking the man in his chest and dropping him to a nearby bed, police wrote.

The situation was just one of a growing number of uses Massachusetts police departments log each year of so-called electronic control weapons — less lethal than guns yet still controversial. Their popularity has exploded among local police.

Police departments reported owning more than 6,000 Tasers at the end of 2016, nearly a 50 percent jump from 2015 and roughly a doubling from just three years earlier, according to newly released data from the state’s Executive Office of Public Safety and Security.

The proliferation of the weapons and a correlating jump in the number of incidents have stoked concerns among some civil libertarians and attorneys, who question whether the growing stockpile is ripe for overuse.

Police, including in Chelsea, point to the devices as an important option to de-escalate a dangerous situation in place of a handgun. Chief Brian Kyes cited the Feb. 22 incident, in which the man, after being stunned, was taken to Massachusetts General Hospital.

“If not for the Taser, he would have taken his own life,’’ said Kyes, whose department has equipped about 75 patrolmen with Tasers. “Our best tool is our ability to communicate. But if drugs or alcohol are in the picture, someone can be the best communicator in the world and the odds are against them. Having a tool [like a Taser] available, it’s less than lethal; that goes a long way.’’

Police in Massachusetts reported a record high of 1,084 Taser uses in 2016, the most recent data available. That was driven largely by a spike in the number of departments using them, 250 in all.

Departments reported owning 6,008 in 2016, or nearly 1,800 more than in the year before — a 42 percent spike.

State Police accounted for a large part of the increase: Officials spent roughly $1 million to buy 895 Tasers that spring, marking the first time they began widely arming troopers with the weapons.

State Police reported 38 deployments in 2016, trailing towns and cities like Barnstable, New Bedford, and Springfield, which had a state-leading 81 uses.

“It gives troopers another option to resolve a confrontation with a hostile and dangerous suspect before that confrontation reaches the point where deadly force may be the only option left,’’ said David Procopio, a State Police spokesman.

Though Tasers are described as devices that deliver less-than-lethal force, there have been fatalities involving their use. In Chelsea, for instance, Dominic Graffeo, 56, died after being tased during a violent confrontation with police officers in 2014.

The Suffolk County district attorney’s office ruled that officers were justified in the use of force.

Ivan Espinoza-Madrigal, executive director of the Lawyers’ Committee for Civil Rights and Economic Justice, said he’s also troubled by other data, including that in 13 percent of Taser contacts in 2016, police gave no warnings.

“To the extent that Tasers are being overused across the state, as demonstrated by the uptick in the number of incidents, it’s concerning because it could contribute to an erosion of trust between law enforcement and civilians,’’ he said.

While growing, the use of Tasers isn’t uniform.

Boston police to date have equipped only members of their SWAT unit with them, and in 2016, they recorded just one incident, according to state data.

The price — Tasers can cost more than $1,000, according to police — has also stopped some cash-strapped departments from buying them, police say.

Others have made the conscious decision not to use them.

Arlington Police Chief Frederick Ryan, whose department doesn’t equip its officers with Tasers, said he has “concerns about the optics’’ of arming patrolmen with them.

“We spend a lot of time and resources in training and equipping our officers in being effective community guardians and problem-solvers,’’ he said.

“We don’t want to give the appearance with our day-to-day community policing officers that they we’re at war with our community.’’

And if the Arlington department needs a less-lethal option, Ryan said, he has the option of calling on the Northeastern Massachusetts Law Enforcement Council’s tactical unit, which is equipped with Tasers.

Matt Stout can be reached at matt.stout@globe.com. Follow him on Twitter at @mattpstout.