AP
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Mexico is developing a cell phone app that migrants can use to alert relatives and local consulates if they believe they are being detained by U.S. immigration authorities, a senior official said Friday.

The move comes in response to President-elect Donald Trump’s threats to carry out mass deportations after he takes office on January 20.

The app was launched for small-scale testing and “seems to work very well,” said Juan Ramón de la Fuente, Mexico’s foreign minister.

He said the app would allow users to press a tab that would send an alert to pre-selected relatives and the nearest Mexican consulate. De la Fuente described it as a kind of panic button.

“If you find yourself in a situation where detention is imminent, press the alarm button and that will send a signal to the nearest consulate,” he said.

U.S. authorities are required to notify home country consulates when a foreign citizen is arrested. Mexico says it has increased consular staff and legal assistance to assist migrants in the legal process related to deportation.

De la Fuente expects the app to launch in January. He didn’t say whether the app has an opt-out tab that would allow someone to cancel an alert if they haven’t actually been arrested.

The government says it has also set up a 24-hour call center to answer questions from migrants.

The Mexican government estimates that there are 11.5 million migrants in the United States with some form of legal residency and 4.8 million without legal residency or documentation.