The cracks were found in one of three Boeing 737NG operated by Garuda Indonesia.

The Indonesian Transportation Ministry has grounded three Boeing 737 NG (Next Generation) planes operated by two airlines following the findings of cracks in the aircraft, an official said on Tuesday.

Quoting Airworthiness and Plane Operation director, Capt. Avirianto, Xinhua news agency reported that the three grounded planes were operated by state-run airlines Garuda Indonesia and private-owned Sriwijaya Air.

Grounding of those planes would continue until further recommendations were issued by Boeing, the director said.

"Furthermore, we advise all national airlines operating Boeing 737NG including Garuda Indonesia, Lion Air, Batik Air and Sriwijaya Air to periodically conduct maintenance program every 3,500 Flight Cycle Number (FCN) that suits with Directorate General of Civil Aviation (DGCA) mechanism," he said.

Cracks in those planes were found in the ones which already had 30,000 FCN, he said.

The cracks were found in one of three Boeing 737NG operated by Garuda Indonesia, while in Sriwijaya Air cracks were found in two of five planes.

The grounding order was issued after inspections carried out by the ministry to follow suit airworthiness directives issued by international aviation agencies to check the Boeing 737NG planes operated by all airlines in the world.

Indonesia has banned operation of Boeing 737 Max 8 plane after a deadly crash of Lion Air flight on October 29 last year that killed all 189 people aboard.