Have you seen Benjamin Song? State and federal agencies have issued a Blue Alert for a suspect who allegedly shot a Texas police officer during the attack of a U.S. Immigration and Customs Enforcement (ICE) detention facility on July 4.

Blue Alerts are issued to help catch people who are believed to have wounded or killed local, state or federal law enforcement officers. Here are the criteria for a Blue Alert: A law enforcement officer must have been killed or seriously injured by an offender.

Phones buzzed across Texas just before 8 p.m. Wednesday with a high-priority emergency alert. But it wasn't about flooding, a storm, or a missing child. It was about a five-day-old shooting at an ICE detention center hundreds of miles away.

Oklahoma Highway Patrol issues Blue Alert in connection with July 4 ambush in Texas. Benjamin Hanil Song, considered armed and dangerous, on Texas' 10 Most Wanted.

As the state mourns the deaths caused by the floods, the disaster is drawing attention to the effectiveness of the Blue Alert system.

Texas is one of several states that use Blue Alerts, but what is it, and how does it differ from AMBER Alerts?

A crisis communication expert says everyday notifications are weakening the impact of life-saving emergency alerts.