Federal agents arrested an Ohio man for selling guns — some of which recovered on their way to Beirut — without a license.

Timothy Cassinger bought and sold hundreds of guns, and invested thousands of dollars in the endeavor from June 2012 to October 2015, says the criminal complaint unsealed Nov. 17.

Court documents detail numerous transactions that Cassinger carried out through private sales, at gun shows and ads posted on the Internet.

The Bureau of Alcohol, Tobacco, Firearms and Explosives was tipped off to Cassinger in September 2014 by Spanish authorities who informed agents that they intercepted 11 guns on their way to Beirut.

After investigating the matter, the ATF learned Cassinger sold the guns through the website Arms List, which hosts gun sales ads posted by private and licensed sellers, to a suspect already being investigated for shipping guns to the Middle East. The suspect had been hiding guns in vehicles aboard cargo containers.

The investigation also revealed that authorities in cities both in and out of Ohio recovered 13 guns that were originally purchased by Cassinger. In November 2014, ATF agents interviewed Cassinger about his gun dealing and informed him of the investigation.

According to federal law, a person who profits through the repetitive purchase and resale of firearms must have a license to do so.

However, Cassinger continued with the transactions, so the ATF issued him a formal warning in January. In the Unlicensed Dealing Warning Letter, the ATF explicitly stated that “continued activity without the required license could result in a recommendation for criminal prosecution.”

About a month later, the ATF flagged Cassinger in the National Instant Criminal Background Check System so agents were notified whenever he initiated a transaction. According to the complaint, agents think he bought 24 additional firearms since they issued the warning letter, but it’s unclear exactly how many since the NICS systems tallies background checks rather than guns purchased. The ATF found an estimated 300 transactions total.

According to financial records reviewed by the ATF, Cassinger spent more than $72,000 on firearms at one store from May 2012 to February 2015, and from November 2012 to the end of 2014, he had made cash deposits totaling $12,543. However, the complaint does not estimate how much total revenue he generated from gun sales.

Starting in September, Cassinger became the subject of an undercover operation and through the end of October, agents met with him on multiple occasions and executed numerous buys. After each transaction, agents would trace the firearms to find out where they originated and they learned had been continuing the process he was warned about.

If convicted, Cassinger could face a $250,000 fine and up to five years in prison.

Story updated at 10 am CST on Nov. 25, 2015