Newark will increase the size of its Emergency Services Unit, which includes SWAT, following the December deaths of four people in a bias shooting in Jersey City, one a police officer, Newark officials said.

Additional personnel will be added to the unit, and it will respond to all violent incidents in the city, Newark Public Safety Director Anthony F. Ambrose said in a statement Thursday.

The SWAT unit was previously used during hostage situations or other major violent emergencies, Ambrose said. The increase in SWAT’s presence will “add another dimension of assurance to the public that we are remaining very vigilant.'”

"The recent uptick in active shooter incidents poses a credible threat to our residents, visitors, corporations and businesses, houses of worship, and to our school children and college students,” Ambrose said. "Due to an increase in shootings nationwide, it’s imperative that we increase our security measures to preserve lives.”

Three civilians and a Jersey City police Detective Joseph Seals were killed in the Dec. 10 attack that ended in a Kosher deli in Jersey City’s Greenville neighborhood. The attackers, David Anderson, 47, and Francine Graham, 50, were killed by law enforcement following several exchanges of gunfire.

Anderson and Graham were killed before they could detonate an explosive device police found in their van, which had the ability to kill or injure people within a 500-foot radius, officials said.

Officials said the shooting stemmed from a hatred of Jewish people and law enforcement, and has been characterized as a bias crime.

Newark SWAT officers train at Joint Base McGuire-Dix-Lakehurst in this 2016 file photo.Patti Sapone | NJ Advance Media

Katie Kausch may be reached at kkausch@njadvancemedia.com. Follow her on Twitter @KatieKausch. Find NJ.com on Facebook.

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