WASHINGTON — The FBI is tracking two serial bank robbers who strike mostly in northern Virginia.

Both men are considered armed and dangerous.

One man, believed responsible for four armed robberies since Nov. 14, showed a gun in each case when holding up two banks in Alexandria, and two in Annandale.

A second man, called the “Sharp Dressed Bandit” on an FBI WANTED poster, has targeted banks in Alexandria, Washington, D.C. and Arlington. Those robberies started Nov.10.

In each of those cases, the FBI is offering rewards of up to $5,000 for information that leads to the robber’s conviction.

Anyone with helpful information should contact the applicable police department: Arlington, at 1-866-411-TIPS (8477); D.C., at 202-727-9099; Alexandria, at 703-746-6711.

The FBI has noticed a distinct trend in bank robberies increasing in the month of December.

It’s unclear whether crooks become more desperate for cash around the holidays, but there have been 13 bank hold-ups since Oct. 31 in D.C. and northern Virginia.

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