BUJUMBURA, Oct 30 (Reuters) - Hundreds of nurses in Burundi began an indefinite strike on Tuesday that paralysed operations in government hospitals, accusing authorities of failing to provide decent pay and benefits promised three years ago.

Nurses in the tiny central African republic earn $35 per month on average. Their strike comes soon after another by teachers seeking higher pay.

"The government was lying to us all the time," Omar Simpenzwe, deputy chairman of the nurses' union, told reporters. "We're on strike to pressure the authorities so that they implement our claims."

Public hospitals turned away most patients and only attended to emergencies. Burundi's hospitals have become more crowded since the government said it would give free health care for children under five and expectant mothers two years ago.

Most public employees are unhappy with their pay and often complain of a hard life.

The confederation of the country's trade unions has warned it would launch a general strike in the coming days unless workers' salaries were boosted.

The government has pledged to give raises of up to 34 percent by next year but the International Monetary Fund has urged the authorities to increase revenues first.

Burundi's economy is suffering, but donors are reluctant to disburse millions of dollars they promised for the country's development until the government exercises better governance and observes human rights.

Finance Minister Clotilde Nizigama said on Monday bilateral donors have agreed to give $75 million for budget support by the end of the year.