Thousands more travellers had their phones, computers and other devices searched at American airports and other border crossings last year, according to new data.

Over the last fiscal year, US Customs and Border Protection (CBP) agents conducted searches of 29,200 arriving international travellers’ electronic devices.

While that represented a tiny fraction of all travellers – 0.007 per cent, according to the agency – it still marked a sharp increase of 59 per cent from the 18,400 people who had their devices searched the year prior.

“In this digital age, border searches of electronic devices are essential to enforcing the law at the US border and to protecting the American people,” CBP official John Wagner said in a statement.

Mr Wagner added that the agency “is committed to preserving the civil rights and civil liberties of those we encounter, including the small number of travellers whose devices are searched” and noted it had updated its search policies with a directive that vows to “protect the rights of individuals against unreasonable search and seizure”.

The policy document also notes that electronic searches “help detect evidence relating to terrorism and other national scurry matters human and bilk cash smuggling, contraband defend child pornography” as well as helping to enforce immigration law.

Protestors rally at JFK Airport against Muslim immigration ban Show all 20 1 /20 Protestors rally at JFK Airport against Muslim immigration ban Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-1 Protestors rally during a demonstration against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump signed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-2 Protestors rally during a protest against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump singed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-3 Protestors rally during a protest against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump singed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-4 SAN FRANCISCO, CA - JANUARY 28: Demonstrators hold signs during a rally against a ban on Muslim immigration at San Francisco International Airport on January 28, 2017 in San Francisco, California. President Donald Trump signed an executive order Friday that suspends entry of all refugees for 120 days, indefinitely suspends the entries of all Syrian refugees, as well as barring entries from seven predominantly Muslim countries from entering for 90 days. 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Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-13 Protestors rally during a demonstration against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump signed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-14 Protestors rally during a demonstration against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump signed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-15 Protestors rally during a demonstration against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump signed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-16 Protestors rally during a demonstration against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump signed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-17 NEW YORK, NY - JANUARY 28: Protestors rally during a protest against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump singed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-18 Protestors rally during a protest against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump singed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-19 Protestors rally during a protest against the Muslim immigration ban at John F. Kennedy International Airport on January 28, 2017 in New York City. President Trump singed the controversial executive order that halted refugees and residents from predominantly Muslim countries from entering the United States. Stephanie Keith/Getty Protestors rally at JFK Airport against Muslim immigration ban jfk-protest-muslim-ban-20 Passengers wait in line to check in at the American Airlines terminal at JFK International Airport August 10, 2006 in the Queens borough of New York City. 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But privacy and civil liberties advocates have challenged such searches as unlawful. In 2017 the American Civil Liberties Union and the Electronic Frontier Foundation sued the government over searches conducted on 11 passengers, arguing that searches and seizures of laptops and cell phones violated the Constitution.