For the past two weeks, nearly 800 city employees got tips from police and emergency management specialists on whether they should run, hide, or fight in the event a shooter storms City Hall.

Mayor Martin J. Walsh ordered the training earlier this month, telling employees in a Jan. 13 letter that recent terrorists attacks in Paris and San Bernardino , Calif., remain “fresh on our minds’’ and that workforce safety and security remain key goals.

“While the need for active shooter training is disconcerting to some, I would be remiss if I didn’t recognize its significance,’’ Walsh said in the letter, obtained by The Boston Globe. “I firmly believe that educating and training City Hall employees will save lives in the event of an emergency.’’

The training sessions come amid growing fears — playing out in presidential politics — about whether workplaces, theaters, and schools are safe.

As an example of a lone attacker, officials said the trainers cited the horrors inflicted on Sandy Hook Elementary School in December of 2012 by a 20-year-old man who entered the school building and killed 20 children and six adults before he committed suicide in Newtown, Conn.

They also brought up the Boston Marathon attacks, perpetrated by two brothers who set bombs next to unsuspecting spectators.

Patrick Brophy, the city’s chief of operations and the point man for the workshops, said both he and the mayor grappled with issues of fear versus public safety but determined that city workers must be armed with a plan in case an attacker strikes.

“Safety is in preparation, and preparation is key,’’ Brophy said, adding he understands that for some, it is a touchy subject. “But we want to make sure our workers are safe at all times.’’

At-Large Councilor Annissa Essaibi George, who attended one of the workshops last week, said the trainers went over what workers could do if someone entered the building and started shooting.

They urged employees to make a mental map of their surroundings, plot escape routes, and figure out places to hide, she said.

During the training, specialists defined an active shooter as an armed attacker who enters a building with a specific target in mind, or one intent on inflicting mass casualties, city officials said.

The trainers also went over protocols used by SWAT teams (neutralizing the attacker) and emergency responders (tending to the wounded).

At the end of the session, the trainers played a video titled “What Would You Do?’’ that showed a shooter interrupting a routine day.

Essaibi George said that after the workshop, she began looking at her office a little differently.

“For some people, this creates some anxieties, but for me personally it gives me tools — and we need these tools,’’ Essaibi George said.

“Unfortunately, this is the reality that we live in now,’’ she added.

Brophy said that the idea for the training sessions began more than two months ago, during a discussion with the mayor about a fire safety drill at City Hall. The mayor suggested doing active shooter training.

Shortly afterward, terrorists struck in Paris, and later, a man and his wife, armed with heavy weaponry, killed 14 of the man’s co-workers in San Bernardino.

Brophy said he enlisted the help of the city’s Emergency Management office and the Boston Police Department with the training.

Both agencies had conducted similar training for the School Department and Brigham and Women’s Hospital, where a lone gunman walked in last year, asked for acardiovascular surgeon by name, and then gunned him down.

Officer James Kenneally, a spokesman for the Boston Police Department, said training has also been conducted at numerous churches and universities.

The “training is about empowering people by arming them with a plan of action in the event they find themselves in an active shooter situation,’’ he said.

Brophy said the city began training department heads, then extended the workshops to all 1,200 employees assigned to City Hall.

Officials expect to soon offer training at other city buildings, Brophy said.

So far, eight training sessions have been held in City Council Chambers, and two others are scheduled, including one next Thursday, he added.

City officials said the training sessions are similar to a pilot effort in the School Department that began in September 2014.

Meghan E. Irons can be reached at meghan.irons@globe.com. Follow her on Twitter @meghanirons.