Information from a Suffolk County​-​reared terrorist who plotted an attack ​on ​the Long Island Rail Road has led to the capture of two Yemeni​ al Qaeda members who battled American forces in Iraq and Afghanistan, ​federal prosecutors say in a new filing.

Bryant Vinas, who was arrested in Pakistan and eventually pleaded guilty to supporting ​al Qaeda in 2009, told agents that hardened terrorists Saddiq Al-Abbadi and Ali Alvi helped him join the group after befriending him in Pakistan, ​the Brooklyn federal ​court papers​ state.

The Medford man traveled to ​Pakistan seeking to join ​a​l Qaeda in 2007 and stayed in a series of safe houses where ​he ​tried to gain the trust of the terror group’s skeptical soldiers.

Vinas first met Alvi in December 2007 at a Waziristan hideout, where he was introduced to an ​al Qaeda trainer who specialized in electronics instruction, court papers state.

But the senior trainer distrusted the American and denied him entry into the group.​ ​Vinas persisted and eventually ran into Alvi and Al-Abbadi in January 2008 at a different safe house, where both men were carrying Kalashnikov​ rifle​s.

Alvi recognized the American ​al Qaeda aspirant and introduced him to Al-Abbadi. Over the course of several weeks, the three men became close, according to the complaint.

Al-Abbadi and Alvi told Vinas that they were both members of ​al Qaeda and had participated in numerous attacks on American forces.

They showed the Long Islander videos of jihadist operations and ​Al-Abbadi boasted of a bullet wound he sustained in a gunfight with US mercenary forces.

After vetting Vinas for weeks, the duo finally agreed to let him into the​ bloodthirsty club. They initially lobbied the Pakistan branch to admit him, but suspicions about Vinas scuttled his application.

Al-Abbadi told Vinas that he had connections to top Yemeni ​al Qaeda leaders and that he would attempt to put in a good word for him​ there​.

But Pakistani leadership eventually reconsidered and let Vinas join their ranks.

The Medford man was then given several weeks of intense training that included lessons on explosives, firearms and projectiles, court papers state.

His coursework completed, Vinas then met with a senior ​al Qaeda leader ​— second only to Osama bin Laden and Ayman al-Zawahiri at the time​ — to receive mission instructions, court papers state. Al-Abbadi was also at that meeting.

The feds ​say Alvi and Al-Abbadi led attacks against American troops and that Al-Abbadi was involved in a 2008 battle that led to the death of an Arm​​y Ranger.

Both men were arrested in Saudi Arabia and transferred to American custody.

Alvi was arraigned in Central Islip on Sunday and Al-Abbadi will face a judge in Brooklyn federal court this afternoon.

“There is no escape from the reach of our law for violent terrorists, especially if they target our military,” US Attorney Loretta Lynch said. “Al-Abbadi and Alvi may have operated in the mountains of Afghanistan, but now they face justice in a courtroom in Brooklyn.”