KINGSTON, Jamaica (CNN) -- Authorities in the Jamaican capital and
                  elsewhere braced Wednesday for a third day of violent protests over gasoline
                  tax hikes that have left at least four people dead and dozens injured.

                  Public opposition began Friday after the government unveiled a 30 percent
                  fuel tax increase, causing gas prices to soar from $1.55 to $2.00 per gallon
                  ($O.41 to $0.53 per liter).

                  Demonstrations were held in Kingston on Monday and quickly spread to
                  smaller towns across the Caribbean island of 2.5 million people.

                  An overnight curfew failed to halt Tuesday's protests. Bus and taxi drivers
                  parked their vehicles and joined the demonstrations, bringing traffic in the
                  capital to a near standstill.

                  Angry crowds hurled stones and robbed motorists who managed to avoid
                  the roadblocks. Other mobs looted stores and banks.

                  Kingston authorities said a pregnant woman was shot and killed Tuesday
                  while looting a hardware store, although it was unclear whether police or
                  looters were responsible. An off-duty soldier died after a confrontation with
                  demonstrators.

                  On Wednesday, a man was killed in a shootout with police and a woman
                  was accidentally shot by stray bullets during an exchange of gunfire between
                  police and protesters in Tawes Pen, St. Catherine, west of Kingston,
                  officials said.

                  As many as 23 people were admitted to Kingston Public Hospital, most
                  suffering from gunshot wounds, said the hospital's executive officer, Carlene
                  Nugent.

                  Prime minister urges calm

                  Prime Minister P.J. Patterson appeared on national television late Tuesday
                  and urged calm. The army has been deployed to contain the crisis and
                  reservists were called to their barracks.

                  Patterson promised to appoint a commission to examine ways to lessen the
                  severity of the hikes, which he said were necessary.

                  Patterson said the increases "provided the best means to continue critical
                  expenditure in transportation, education, health, roads and inner-city
                  projects."

                  Opposition leader Edward Seaga said he would continue to protest the
                  government budget. His Jamaica Labor Party planned a march in Kingston
                  on Wednesday.

                  "The situation is very serious, but the people are very serious too and have
                  no intention of giving up," Seaga said. "They are determined that they must
                  have a positive response before they withdraw their demonstration."

                  Flights, cruises canceled

                  The protests have also had a negative impact on the tourist industry. Airlines
                  canceled some flights Wednesday and the U.S. Embassy warned American
                  citizens and tourists to stay off the streets.

                  Several cruise ships also have canceled trips. Rioters looted shops and
                  burned a large sugar plantation in Montego Bay, a popular tourist destination
                  in the northwest.

                  Business leaders have shown little support for the government and are
                  worried that the protests will have a more devastating impact on the
                  economy than the actual tax increases.

                  "The gas tax will be a joke compared to the money we are going to lose in
                  tourism," said entrepreneur Gordon "Butch" Stewart, who owns the Sandals
                  hotel resort chain.

                           The Associated Press and Reuters contributed to this report.