Singapore, July 8 (Reuters) - Ship tracking data showed that at least four oil and gas tankers turned back from attempting to cross the Strait of Hormuz, after renewed attacks on vessels in the strategic waterway raised concerns about safety and security.

The change in these tankers' routes comes after a Qatari liquefied natural gas tanker and a Saudi-flagged crude oil tanker were damaged near the strait on Tuesday, following reports that Iran had fired missiles at ships in the waterway, prompting maritime authorities to raise the threat level for ships transiting the strait to "severe".

Data from analytics firm Kpler and the London Stock Exchange Group showed that the LNG tankers Al Ghariya, Duhail, and Al Ruwais were all moving slowly westward toward the Strait of Hormuz before changing course and turning away late Tuesday. The three tankers, operated by Qatar Energy, were empty and heading toward Qatar's export terminal at Ras Laffan to load cargoes.

Meanwhile, data from the London Stock Exchange Group and Kpler also showed that an Indian-flagged tanker, carrying 2 million barrels of Kuwaiti crude oil loaded late last week, turned back off the Omani tip of the Strait of Hormuz on Wednesday.