Dunbar Armored Inc., a Hunt Valley-based security and cash management firm that employs 5,400 people, will be sold to rival The Brink’s Co. for about $520 million in cash.

Brink’s, based in Coppell, Texas, announced the deal Thursday.

Dunbar, a 95-year-old family-owned business, has grown into the fourth-largest U.S. cash management company, with 78 branches and a fleet of more than 1,600 armored cars. The privately held firm had revenue of about $390 million in the past year, Brink’s said.

Dunbar’s focus on small-to-medium-sized retailers and financial institutions will help expand and complement Brink’s customer base, the company said.

“Dunbar and its employees have built an excellent reputation and a loyal customer base over the last 95 years under generations of family leadership,” said Doug Pertz, Brink’s president and CEO, in an announcement. “The combination of our two companies, each with an impressive heritage, forms a solid foundation for future success.”

Kevin Dunbar, Dunbar’s CEO and a third-generation owner, said his father “entrusted me to continue to grow the business to levels that we never thought could be reached. … We are delighted with the Brink’s transaction and are confident that Brink’s will continue the Dunbar success.”

Dunbar did not respond to a request for more information about how the deal might affect its local operations. Dunbar had as many as 800 employees in Maryland in 2015.

Dunbar traces its roots to 1923 in New England, when a family member started the armored car company Mercer and Dunbar. James L. Dunbar started Federal Armored Express in Baltimore in 1956 and later added security guard and cash vault services, alarm systems, ATM cash management systems and other services.

The deal is expected to close by the end of the year.

lorraine.mirabella@baltsun.com

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