CAIRO, July 26 (Reuters) - Egypt's security forces killed four suspected militants and arrested two others thought to have carried out an attack on a checkpoint south of Cairo earlier this month, an interior ministry statement said on Monday.

Egypt has been battling an Islamic State-led insurgency in the Sinai Peninsula that has killed hundreds of soldiers and police officers since 2013. But attacks have increasingly moved into the mainland in recent months.

The interior ministry said security forces raided two hideouts in western Cairo, leading to an exchange of gunfire between them and the suspected militants. The statement did not say when the raid took place.

The checkpoint attack in the al-Badrasheen area of Giza province, 30 km (20 miles) south of the capital, killed two officers and three conscripts.

This month, Egypt saw one of the worst attacks on its security forces in years, when 23 soldiers were killed after two suicide car bombs were detonated in North Sinai.

(Reporting by Mostafa Hashem; Writing by Nadine Awadalla; Editing by Hugh Lawson) ((Nadine.Awadalla@thomsonreuters.com;))