A Sudanese migrant accused of walking the entire length of the 31-mile (50-kilometer) Channel Tunnel from France to Britain has pleaded innocent to charges in a court appearance.

Abdul Rahman Haroun, 40, denied causing an obstruction to an engine or carriage when he appeared at Canterbury Crown Court in Kent via video link. He spoke through an Arabic interpreter.

Kent police say Haroun, 40, allegedly slipped past officers at the entrance of the tunnel and dodged hundreds of security cameras before being spotted by British security guards near Folkestone.

Eurotunnel says the incident was extremely dangerous, with trains travelling up to 100 miles (160 kilometers) an hour.

Authorities have stepped up security, improved fencing and increased border patrols amid an unprecedented surge in migrants trying to reach Britain from France.