CAIRO - Egypt on Friday launched a major security operation involving the army and police against "terrorist and criminal elements and organisations" across the country, the army spokesman said.

The army spokesman said the operation covers areas in Sinai, the Delta and the Western Desert and it follows a three-month deadline set by President Abdel-Fattah al-Sisi to crush a years-long Islamist insurgency.

"The law enforcement forces began this morning implementing the comprehensive confrontation against the terrorist and criminal elements and organisations in northern and central Sinai," an army spokesman said in a televised statement.

The army spokesman said the operation will involve operational and training manoeuvres to tighten state control on the country's crossing points with neighbouring countries, and urged full cooperation with the law enforcement forces involved in the operation.

Residents reported hearing extensive air activities above the Suez Canal city of Ismailia, which is close to the area of operations in northern and central Sinai.

Security forces have for years battled an Islamic State insurgency in North Sinai that has killed hundreds of soldiers and police. The militants have expanded their targets to include civilians over the last year or so.

(Reporting by Mostafa Hashem, writing by Sami Aboudi; Editing by Matthew Mpoke Bigg) ((Sami.Aboudi@thomsonreuters.com; +97143918301;))