COLOMBO: Sri Lanka announced Wednesday it will give a one-month free visa on arrival to visitors from nearly 50 countries in its latest effort to revive the island nation's lucrative tourism industry that was badly hit by the Easter bomb attacks that killed 263 people.

Tourism Minister John Amaratunga said tourists or those visiting for business purposes could get their free visa on arrival or applying online. The measure will be effective for six months, starting from Thursday.

He said the government expects a substantial increase of tourists from the move. "If it is not beneficial we will suspend this program," he said.

Because of the measure, the government may lose about 4.3 billion rupees ($24 million) in revenue it could have earned from charging visas.

Sri Lanka charges $35 for a one-month tourist visa or $20 for nationals from South Asia.

Seven suicide bombers from a local Muslim group, National Thowheed Jammath, attacked three churches and three luxury hotels on April 21, killing 263 people, including 45 foreigners mainly from China, India, the U.S. and Britain.

Many tourists cut short their holidays while others cancelled their bookings, dealing a severe blow to the tourism industry, the country's third-largest foreign currency earner after remittances from overseas workers and textile and garment exports.

According to government data, tourist arrivals declined by about 45% in July from a year earlier. However, arrivals in July, which stood at 117,000, showed a moderate increase compared to 63,072 in June.

Prime Minister Ranil Wickremesinghe assured that Sri Lanka is now safe for tourists and "security has returned to normalcy."

He said Wednesday that all those involved in the deadly attack are in custody and "even those who had a longstanding association with them, although they have not involved in the attack, are also being questioned and some have been detained and some have been released."

About 200 have been detained and police are continuing their investigations, he said.

The government has introduced many measures to revive tourism that include reducing airline ground charges, aviation fuel prices and departure fees for at least six months. It set a one-year moratorium for repayment of loans for tourism-related businesses and cut interest rates on new loans. Hotels, too, have announced attractive packages with discounts up to 60%.

"We would like to promote Sri Lanka as a destination which is safe for people to visit and also we are giving them the type of concessions and rates which they may not get for a long, long time," said Wickremesinghe.

About 2.3 million tourists visited Sri Lanka in 2018 when 29 airlines offered 300 flights per week. After the attacks, 41 fights per week were cancelled, amounting to a loss of 8,000 passenger seats. Several airlines have reinstated their normal schedules since then, but others have not.

Tourism accounts for 4.9% of Sri Lanka's GDP. Around half a million Sri Lankans depend directly on tourism and 2 million indirectly.

The government currently predicts $3.7 billion in revenue from tourism this year, down from an initial forecast of $5 billion.