synagogue and Black students at a local high school.

Prosecutors in North Carolina on Monday revealed two teenage gunmen, who in May attacked members of a mosque in San Diego, had planned to also attack a San Diego synagogue and Black students at a local high school.

Instead, Amin Abdullah, a security guard fired a shot that struck one of the gunman and likely prevented the pair from further wreaking havoc on the San Diego County community, according to Forsyth County District Attorney Jim O'Neill said. Instead of advancing on the mosque and the Islamic Center's student-filled school, the shooters drove away, stopping to shoot a landscaper, who survived, before turning the guns on themselves.

The shooters had planned to attack the Kehilat Ariel Messianic Synagogue, which is about 1.5 miles from the Islamic Center of San Diego where Abdullah, Mansour Kaziha and Nadir Awad were killed on May 18.

The revelation came to light Monday during a news conference announcing the grand jury indictment of a 17-year-old girl who is accused of helping disseminate a livestream of the shooting and the hate-filled manifesto of the gunmen, O'Neill said. Sarah Lindsay Santiago, 17, is being tried as an adult due to North Carolina law on three counts of murder by aiding and abetting and one count of conspiracy.

San Diego police confirmed the statements made by the Forsyth County district attorney but would not disclose any further information regarding the intended targets "as not to legitimize their alleged plans."

A teenage girl from North Carolina was indicted Monday for allegedly aiding and abetting two teenage gunmen who killed three people in a mass shooting at the Islamic Center of San Diego in May, officials said. NBC 7 has more.

NBC San Diego spoke to a Rabbi Barney Kasdan of the Kehilat Ariel Messianic Synagogue on Monday evening. He was not surprised the synagogue came up on the shooters’ radar based on its short distance from the Islamic Center.

“Somehow God directed away from Kehilat Ariel if that was their intention," said Rabbi Kasdan.

New details were released on Monday involving the San Diego mosque shooting, including how a North Carolina teen took part. According to the investigation, the shooters also planned an attack on a local Jewish temple and a high school. NBC 7's Dave Summer reports.

O'Neill said the attack on the Islamic Center of San Diego was believed to be the first to be "ideologically-motivated" in a century, and he urged parents to pay attention to what their kids are doing online.

"This underground subculture of hate, they listen to each other, they talk to each other on coded platforms," O'Neill said. "It radicalizes one another to the point where they carry out these horrific crimes of violence and murder."

At the Islamic Center of San Diego, a few signs of support still hang on the fence as the community. Members of the mosque community were surprised to find out an arrest was made in North Carolina. Some are calling for accountability closer to home.

"Who knew about this incident locally? Right. And why aren't there any local people that are being held accountable?" community member Khalid Alexander said.

Imam Taha Hassane, of the Islamic Center of San Diego, says many in the community still have questions about how that fateful day came to happen, and what can be done to prevent it from happening again.

"Our martyrs deserve, dignity, deserve answers. And their families deserve answers," Hassane said.

Hassane said members of their community group are still scared to return to the mosque or to bring their kids to its school. The Islamic Center released a statement to its community members following the indictment reassuring them that it was not connected to any new threats against their center. Hassane urged them to not succumb to the fear.

"This is our city. We love our city. We're a part of this city," he said. "And we're not going to be, made to be afraid by any type of hateful rhetoric."

Rabbi Kasdan, meanwhile, is confident in security protocols at his synagogue. He says armed guards are visible at every major event at the temple. A security guard also sits outside the Islamic Center mosque.

“Even though we are very different communities, sometimes politics get in the way but there is no place for hate," Kasdan said.

The teenage girl's indictment is a relief to Rabbi Kasdan.

"It just goes to show what we all are understanding that the dangers of social media spreading hate messages. I’m glad they found, whoever she is and anyone who assisted in this terrible crime," Kasdan said.

San Diego FBI Special Agent-in-Charge Mark Remily said the indictment should send a message that whether you are physically involved in an act of violence, on the scene, or 2,000 miles away in support of it, will be held accountable and, in this case, the charges are as serious as they get.