A giant Buddha statue still under construction, said to be the tallest in northern Vietnam, collapsed out of a sudden on Tuesday, in what could be a case of improper design.

Around ten builders were at the construction site of the 45-meter-tall statue at Sac Thien Vuong Pagoda in Quynh Phu District, Thai Binh Province when the concrete structure weighing hundreds of metric tons gave way.

Nguyen Khac Than, the district deputy chairman, confirmed to Tuoi Tre (Youth) newspaper early Wednesday that the structure had “completely come down.”

While the reason for the collapse remains unknown, it is reported that the design of the structure has been improperly done.

Than said the district administration has tasked relevant agencies with identifying the cause of the cave-in.

He also said whether the statue is the tallest in northern Vietnam is not confirmed now.

“It is also incorrect to say, as initial information went, its construction is funded by the state budget,” he added.

Buddhists have donated to build the statue over the last few years and there has yet to be any record of the total construction cost, according to the chairman.

Locals said construction started around three years ago, and the cost must have totaled hundreds of billions of dong so far. (VND1 billion = US$45,935).

Sac Thien Vuong is arguably the largest pagoda in the area, where thousands of Buddhist pilgrims visit on an annual basis.