A tsunami warning was erroneously sent to some East Coast mobile phones Tuesday as lawmakers in Washington gathered to look into emergency alert problems, including last month’s false notification of a missile attack in Hawaii.

The National Weather Service’s National Tsunami Warning Center issued a “routine test message” around 8:30 a.m., and the message was released by “at least one private sector company” as an official tsunami warning, Susan Buchanan, spokeswoman for the weather service said in an email. She didn’t identify the company.

The result was “widespread reports of tsunami warnings received via phones and other media across the East Coast, Gulf of Mexico, and the Caribbean,” Buchanan said.

The National Weather Service mistakenly inserted a code indicating the tsunami alert was genuine, causing the message to route automatically to AccuWeather Inc. users, said Barry Lee Myers, chief executive officer of the closely held forecaster based in State College, Pennsylvania. “It was not our mistake,” Myers said.

Soon after Tuesday’s false alert the weather service’s Twitter account for New York City posted a message saying, “***THERE IS NO TSUNAMI WARNING***”.

The Weather Channel app in a tweet said it also relayed the warning. A notification for a tsunami warning was sent “to thousands along the East Coast” who subscribe to weather warning alerts, the service said in a statement posted online. It later told readers to disregard the message and blamed a National Weather Service mistake. The tsunami warning didn’t appear on the Weather Channel viewed on cable systems.

The Federal Communications Commission is looking into Tuesday’s incident, a spokesman said in an email.

Lawmakers said such incidents, including Hawaii’s Jan. 13 false alarm, could erode public confidence in the warning system, causing people to ignore the messages.

“Unfortunately, there have been erroneous emergency alerts sent to the public. That undermines the confidence in the system,” Representative Dan Donovan, a New York Republican, said at a congressional hearing. “We saw an example of this just this morning.”

Myers, of AccuWeather, said he had notifed the weather service after a similar incident in 2014. “It’s a problem AccuWeather has warned the weather service about for years,” Myers said.

Donovan, the chairman of the House Emergency Preparedness, Response, and Communications Subcommittee, asked if training or procedures need to be improved.

“For the public alerts and the warnings to be effective, the public has to be able to trust them,” said Representative Donald Payne Jr., a New Jersey Democrat. “False alerting can be very dangerous as it can lead to alert apathy, confusion and unnecessary panic.”

In the Hawaii incident, a state worker mistakenly believed a ballistic missile attack was under way, federal regulators said last week. Residents anxious about months of nuclear saber-rattling between U.S. President Donald Trump and North Korea’s Kim Jong Un were sent into a panic. The FCC is still investigating the Hawaii alarm.