A Chinese national was arrested on Tuesday for allegedly shipping weapons and ammunition from Long Beach, California, to North Korea.

Shenghua Wen, 41, who had been “illegally residing in the United States,” was charged with conspiracy to violate the International Emergency Economic Powers Act, according to a press release from the U.S. Attorney’s Office for the Central District of California. The press release described Wen as being a Chinese nation who had overstayed his student visa in the U.S. and who was “therefore prohibited from possessing any firearms or ammunition.”

Violating the International Emergency Economic Powers Act is described as a “felony that carries a statutory maximum sentence of 20 years in federal prison,” according to the press release.

Wen reportedly “exported to North Korea shipments of firearms, ammunition and other military items” that had been “concealed inside shipping containers” from Long Beach. The containers were then shipped from Long Beach to Hong Kong and from Hong Kong to North Korea.

“It is essential that we protect our country from hostile foreign states that have adverse interests to our nation,” U.S. Attorney Martin Estrada said in a statement. “We have arrested a defendant who allegedly acted at the direction of the North Korean government by conspiring to illegally ship firearms, ammunition, and other military equipment to North Korea.”

The press release noted that “an affidavit filed on November 26 with the complaint” claimed that Wen had “obtained firearms, ammunition, and export-controlled technology with the intention of shipping them to North Korea”:

According to an affidavit filed on November 26 with the complaint, Wen obtained firearms, ammunition, and export-controlled technology with the intention of shipping them to North Korea — a violation of federal law and United States sanctions against that nation. Wen and his co-conspirators allegedly exported shipments of firearms and ammunition to North Korea by concealing the items inside shipping containers that were shipped from Long Beach through Hong Kong to North Korea.

Wen’s arrest comes months after law enforcement officials “seized” from Wen’s residence on August 14, “two devices that he intended to send to North Korea for military use.” One was reportedly a “chemical threat identification device” and another was a “hand-held broadband receiver that detects eavesdropping devices.”

On September 6, law enforcement officials seized from Wen’s residence “approximately 50,000 rounds of 9mm ammunition that Wen allegedly obtained to send to North Korea,” according to the press release.

The criminal complaint claimed Wen had “told investigators that North Korean government officials wired him approximately $2 million to purchase firearms and other products” for them, according to Fox News.

Wen also “purchased an armory and a federal firearm license for $150,000,” and had other people “make the purchases” of firearms, according to the complaint, the outlet reported.

“The results of today’s arrest and search warrants are a testament to HSI and our partner agencies commitment to national security and protecting our sensitive technology,” Shawn Gibson, the Special Agent in Charge of Homeland Security Investigations (HSI) San Diego said in a statement. “It is a federal crime to illegally obtain and export certain US technologies by foreign countries and those who seek to circumvent the law will be thoroughly investigated.”