The perilous contest between the United States and Iran for influence in the Middle East escalated dramatically on Thursday as two tankers were targeted in suspected attacks near the strategic Strait of Hormuz, a vital waterway for global oil shipments.

Two oil tankers near the strategic Strait of Hormuz were reportedly attacked on Thursday, an assault that left one ablaze and adrift as sailors were evacuated from both vessels and the U.S. Navy rushed to assist amid heightened tensions between Washington and Tehran.

Hong Kong police fired tear gas and high-pressure water hoses against protesters who had massed outside government headquarters Wednesday in opposition to a proposed extradition bill that has become a lightning rod for concerns over greater Chinese control and erosion of civil liberties in the semiautonomous territory.

China will respond firmly if the United States insists on escalating trade tensions, the foreign ministry said on Tuesday after U.S. President Donald Trump said further tariffs were ready to kick in if no deal was reached at June’s G20 summit.

As its nuclear deal with world powers unravels amid heightened tensions with the United States, Iran will see a week of high-stakes diplomacy capped by the first visit of a Japanese prime minister to Tehran since the 1979 Islamic Revolution.

Since the horror of the 9/11 attacks perpetrated by al-Qaeda and the emergence of the Islamic State, the U.S. has been fixated on preventing the next major terror attack. However, the focus is slowly shifting toward stopping lone-wolf attacks.