Mahmud Hassan, a retired customs officer, and two others were sentenced to 16 years in jail by the Federal High Court in Lagos for conspiring to illegally import 661 pump-action rifles.
Oskar Okafor, Donatus Achinulo, and Mahmud's company, Hassan Trades Limited, are the other two people convicted with Hassan.
Justice Ayokunle Faji, the sitting court, acquitted and discharged another defendant, Abdulahi Danjuma, of all charges.
Justice Faji found the first, second, and third defendants guilty of conspiracy and sentenced them to eight years in jail each on count one.
As a result, the court ruled that the offenders' property be forfeited to the Nigerian government.
The court also ruled that the business used to smuggle the weaponry, Hassan Trading Limited, be wound up and its assets forfeited to the federal government.
The fifth defendant, on the other hand, was released and acquitted by Justice Faji.
The judge stated in his decision that the convicts' crime jeopardizes the country's security.
He went on to say that, despite the fact that the relevant provisions of the law for the crime for which they were accused and convicted called for life imprisonment, the court uses its discretion.
The trial judge stated that while he would not impose the maximum penalty, the offenders must be held accountable to act as a deterrence to other would-be criminals.
Justice Faji was particularly critical of the second convict, a retired customs officer, noting that the harmful consequences of the container not being stopped and the guns falling into the hands of criminals in society could only be imagined.
The accused imported the guns from Turkey through the Apapa harbor in Lagos, according to the Attorney-General of the Federation and Minister of Justice, Abubakar Malami.he however went on to say that the weaponry were shipped in a 40-foot container that they misrepresented as steel doors.
To help the smuggling of the guns, the prisoners allegedly fabricated documents such as a bill of lading, a Form M, and a Pre-Arrival Assessment Report.
The defendants also allegedly faked a bill of lading issued in Istanbul on January 9, 2017, falsely claiming that it was issued in Shanghai, China, according to the prosecution.
He claimed they planned to avoid paying customs charge by loading the container with "steel door" instead of guns.
They were also accused of offering a bribe of N400,000 to a Nigeria Customs Service agent attached to the Federal Operative Unit in order to avoid a "100% search on the container with number PONU 825914/3."
The prosecution also claimed that Hassan, the first convict, bribed government officials at the Apapa port with N1 million to avoid a customs search.When the charges were read to them, they pleaded not guilty.
The punishment will be served consecutively, according to the judge.