BANGKOK — Thailand is counting the multibillion dollar cost of nationwide flooding that has killed nearly 270 people and may yet cause more havoc as waters threaten to engulf the country’s capital.

Bank of Thailand Governor Prasarn Trairatvorakul said a preliminary estimate by the central bank shows economic losses from flooding that began in late July range from $1.9 billion to $2.6 billion.

That figure doesn’t include damages to assets or reconstruction costs and is expected to rise as the floodwaters surge toward Bangkok, a city of about 10 million people.

Prime Minister Yingluck Shinawatra and Bangkok officials pleaded today with the city’s residents not to panic as workers raced to complete three critical flood walls with only one or two days to go before the swollen river bursts its banks.

Supermarket shelves have been cleared by shoppers of basic items such as rice, bottled water, pork and chicken.

The disaster is a further blow to Thailand’s electronics and auto industries, which have only just recovered from the tsunami in Japan that knocked out suppliers of critical components.

A dive in Thailand’s auto production caused the economy to shrink in the second quarter.