The Lao News Agency says 23 people have been missing after a Laotian army helicopter had an accident after leaving the capital on Monday.

State-owned news agency KPL said Wednesday that four crew members and 19 passengers were on the helicopter that lost communication with the aviation control center shortly after it took off from Vientiane.

It cited the Ministry of National Defense as saying airborne access to the scene was impossible due to bad weather and only ground search efforts were conducted.

The news agency said the helicopter was en route to Xiengkhuang and Houaphanh provinces in the northeast and the east of the country.

A military plane crash a year ago killed at least five people, including the country's then-defense minister.