By Ruma Paul

DHAKA (Reuters) - Bangladesh police shot and killed a suspected militant who tried to cross a security checkpoint on a motorcycle armed with explosives early on Saturday, the latest in a string of security threats since a deadly attack on a cafe in July.

Bangladesh's counter-terrorism Rapid Action Battalion (RAB) said some of its officers opened fire when a man riding a motorcycle tried to break through a checkpoint in Dhaka's Khilgaon area.

"Several bombs were found attached to his body," the RAB's Legal and Media wing chief Mufti Mahmud Khan told Reuters, adding that an apparent suicide attack could have been foiled.

He said two officers were wounded in the incident but it was not clear how they got hurt.

The latest incident came a day after a suicide bomber blew himself up at a security forces base near the international airport in the South Asian nation's capital, Dhaka.

Bangladesh has stepped up security at all airports and prisons across the country after Friday's attack. The most serious recent attack came last July, when gunmen stormed a Dhaka cafe and killed 22 people, most of them foreigners.

On Thursday, four suspected members of an Islamist militant group blamed for that attack were killed during a police raid in the southeastern town of Chittagong.

Al Qaeda and the Islamic State militant group have made competing claims over killings of foreigners, liberals and members of religious minorities in Bangladesh, a mostly Muslim country of 160 million people.

Authorities have consistently ruled out the presence of such groups, blaming domestic militants instead. However, security experts say the scale and sophistication of the cafe attack suggested links to a wider network.

Police have killed more than 50 suspected militants in shootouts since the cafe attack, including the man they say was its mastermind, Bangladesh-born Canadian citizen Tamim Ahmed Chowdhury.

(Editing by Julia Glover)