BRASILIA (Reuters) - Brazil’s Forjas Taurus SA, the largest weapons maker in Latin America, shipped guns to the son of a known arms trafficker in July 2015, three months after the United Nations imposed an arms embargo on his allies in Yemen’s civil war, according to a U.N. report released last week.

The U.N. document cited and expanded upon a Reuters report in September that detailed the charges in Brazil against former executives at Taurus who allegedly shipped handguns in 2013 to Fares Mohammed Hassan Mana’a, a Yemeni arms smuggler sanctioned for dealings around the Horn of Africa for more than a decade.

U.N. experts on the conflict in Yemen said an investigation turned up several red flags in the sale of the handguns, which were registered for use in Djibouti but allegedly destined for black markets in the region.

Authorities in Saudi Arabia seized an arms shipment in November 2015 before it got to Djibouti, on suspicion the arms were bound for Houthi forces fighting a Saudi-backed coalition in Yemen, according to the report.

“Had Taurus ... exercised due diligence then they would have identified aspects of this arms purchase that were suspicious in relation to the targeted arms embargo on Yemen, and could have stopped the shipment,” wrote the experts.

Responding to the U.N. report, the gun maker told Reuters in an email that the transaction followed all protocols required by Brazilian and international law, and the company halted any further shipments involving Djibouti after learning of concerns about the deal.

“Taurus had no grounds to distrust the buyers,” it said.

The U.N. report questioned why an end-user certificate from Djibouti cleared the transfer of up to 80,000 pistols to the Ministry of Defense, when the country’s armed forces consist of just 16,000 active personnel and 9,500 reservists.

Investigators also said the company listed as importer on the certificate appeared on none of the shipping, financial or legal documentation for the arms transfer. Instead, the report said, Taurus worked with Itkan Corporation for General Trading, a Yemeni firm owned by Adeeb Mana’a, son of the arms trafficker.

The transfer was “designed to circumvent normal security and customs controls,” the UN report concluded.

The U.N. experts said they could not find a valid address for Itkan in Djibouti, nor did the government there respond to a request for the company’s registration and banking details.

Brazil’s Defense Ministry and Djibouti’s Foreign Ministry did not respond to requests for comment about the U.N. report. The Mana’a family and Itkan Corp could not be reached for comment.

Taurus told Reuters it did not know why Itkan had been selected as an intermediary for the shipment in Djibouti and it was unaware at the time of restrictions against the company or its owner.

Taurus also said it had not taken part in any efforts to evade security controls and has since reinforced internal controls to avoid similar situations. Taurus noted that the April 2015 Yemen arms embargo was not implemented in Brazilian law until July 2016.