SEATTLE — A federal grand jury has indicted two men on nine conspiracy and weapons-related charges in connection with an alleged plan to carry out a terrorist attack on a military processing station in Seattle.

The indictment was issued Thursday just hours before the men were scheduled to appear for a preliminary hearing in U.S. District Court in Seattle. That hearing will no longer be held.

Instead, Abu Khalid Abdul-Latif, 33, a Seattle man formerly known as Joseph Anthony Davis, and Walli Mujahidh, 32, formerly known as Frederick Domingue Jr., of Los Angeles, are to be arraigned on the indictment.

The indictment for the most part follows a criminal complaint filed when the men were arrested on June 22, charging them with conspiracy to kill government workers and officials, conspiracy to use a weapon of mass destruction (a grenade) and weapons charges that could result in life prison terms.

However, the grand jury added a charge of soliciting a crime of violence against Abdul-Latif.

The men were arrested after Seattle police received a tip from an informant that they were planning an attack against Joint Base Lewis-McChord. The unidentified paid informant, a felon, infiltrated the alleged conspiracy at the behest of the FBI and police.

The men changed their target to the Military Entrance Processing Station on East Marginal Way, and planned to storm the facility armed with automatic rifles and grenades on the day after the Fourth of July.

According to the FBI, the informant recorded conversations with the men in which Abdul-Latif said he hoped the attacks would inspire other young Muslims to rise up against the West.

The plan involved the informant supplying the men with weapons, which had been disabled.

Abdul-Latif, according to court documents and law enforcement sources, was “self-radicalized” and had chosen Joint Base Lewis-McChord at least partly because Stryker soldiers there are being court-martialed for allegedly murdering Afghan civilians.

Abdul-Latif served time for robbery in Washington. Mujahidh has a history of mental illness.