Authorities have arrested the 14-year-old girl who ignited an Internet firestorm after tweeting a threat at American Airlines Sunday.

Police in Rotterdam, Netherlands tweeted Monday morning from their official account that the Dutch girl has been arrested and that the investigation into the matter continues.

The girl, who identified herself as Sarah online, initially tweeted at American Airlines that she was a member of Al Qaeda and was going to “do something really big” on June 1. She later said she was joking.

Image source: Twitter

Image source: Twitter

The airline tweeted back at her saying they “take these threats very seriously” and said that her IP address and details would be forwarded to security and the FBI.

Image source: Twitter

Image source: Twitter

Both Sarah and American Airlines eventually removed their initial tweets. Sarah’s account was later suspended by Twitter.

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