Two terrorist suspects arrested by the F.B.I. in Southern California were charged Friday with conspiring to support the Islamic State after agents overheard them saying on their tapped phones that it would be "a blessing to fight for the cause of Allah."

Muhanad Badawi, 24, and Nader Elhuzayel, 24, both from Anaheim, California, were arrested separately by the F.B.I. a day earlier.

Elhuzayel was arrested at the Los Angeles International Airport by F.B.I. agents who found him in possession of a one-way ticket to Tel Aviv, with a stop in Istanbul, Turkey, a criminal complaint filed in the Central District of California showed.

The agents said Elhuzayel admitted to them after his arrest that he actually had no plan to go to Israel but planned instead to "travel to the Islamic State, pledge allegiance to ISIL, and defend ISIL against attackers."

Badawi was arrested after he was found to have allowed Elhuzayel to use his credit card to purchase the ticket to the Middle East, a statement issued by the U.S. Attorney's Office for the Central District of California said.

The complaint cited phone conversations between Badawi and Elhuzayel where they "discussed how it would be a blessing to fight for the cause of Allah, and to die in the battlefield." The complaint noted that the two referred to ISIS as "we."

An affidavit released by the Department of Justice in support of the criminal complaint against the two detailed a scheme where Badawi and Elhuzayel made use of social media to talk about ISIS and terrorist attacks, with the two expressing their desire to die as ISIS martyrs.

The affidavit said Elhuzayel expressed his support on social media for Elton Simpson, one of the two men killed in a shootout with police after trying to attack an event in Garland, Texas, earlier this month.

The affidavit said last May 3, Elhuzayel saw a tweet from Simpson. In the tweet, Simpson said he and his "bro" had pledged allegiance to the leader of ISIS. In response, Elhuzayel tweeted his support for the attempted attack and praised Simpson as a "martyr."

When Badawi expressed concerns about ISIS struggling due to airstrikes by coalition forces, Elhuzayel responded that they had to be patient, adding, "can you imagine when al-Qaeda joins with Islamic State?"

Badawi responded, "We will be huge."

The two men also discussed local Muslim leaders. Elhuzayel complained that these leaders were not "legitimate" because they believed in democracy and were not fighting for an Islamic state.

They discussed where in the Middle East they would rather be, and Elhuzayel said he wanted to fight and did not want to be in the United States.

If convicted, Badawi and Elhuzayel each would face a statutory maximum sentence of 15 years in prison.