DAR ES SALAAM, July 9 (Xinhua) -- Tanzanian authorities said on Monday they have started verifying registration certificates and licenses for firms that are engaged in tourism businesses in the east African nation.

Gaudence Milanzi, the Permanent Secretary in the Ministry of Natural Resources and Tourism, said the move was aimed at identifying and removing all unregistered and unlicensed firms from doing the tourism business.

Milanzi said in a statement that unregistered and unlicensed firms have been linked to incidences of fraud including conning and causing unnecessary inconveniences to tourists.

Milanzi said such incidences were tarnishing Tanzania's image to tourists around the globe.

The statement added that the government was currently issuing registration forms to tourist firms for 2018, warning that those seeking to register should provide valid and accurate information.

The 2016 International Visitors' Exit Survey Report indicated that the number of tourists who visited the country, east Africa's second largest economy, continued to rise.

The report showed that Tanzania hosted at least 1,284,279 tourists in 2016, compared to 1,137,156 in 2015, which was an increase of 12 percent.

The report showed revenues from the tourism industry have been increasing year after year with 2.1 billion U.S. dollars in 2016 against 1.9 billion U.S. dollars in 2015.

Tourism has been Tanzania's largest foreign exchange earner since 2012, contributing an average of 2 billion U.S. dollars annually, which is equivalent to 25 percent of all exchange earnings, according to government data.