Four men have been arrested over last month's suicide attack on the Marriott Hotel in the Pakistani capital, police said Friday.

The four were suspected of "indirect involvement" in the massive blast at the hotel in Islamabad, the city's police chief Ahmad Latif said. They are the first known arrests in relation to the bombing.

The Sept. 20 attack killed 54 people and was a bloody reminder of the gathering threat posed by Islamist militants in nuclear-armed Pakistan.

Latif said the men were arrested in different parts of the eastern province of Punjab, but gave no more details.

The men were brought before an anti-terrorism court on Friday where a judge gave police permission to question them for one week.

Militants in Pakistan have launched more than 90 suicide attacks on civilian, military and Western targets since July last year, killing nearly 1,200 people, according to military statistics.

Authorities have said they suspect terrorists based in the tribal regions close to Pakistan's border with Afghanistan of carrying out the Marriott blast.

Click here for photos of the blast. (Warning: some graphic images)