At times on Monday, Haitian police fired shots into the air to disperse large roving bands of scavenging looters as they swarmed across the capital.
Nearly a week has passed since Haiti was rocked by last Tuesday's massive 7.0-magnitude earthquake, in which 200,000 people are believed to have been killed. Delays in the delivery of supplies to hundreds of thousands desperate for aid is stoking unrest.
Transportation bottlenecks, bureaucratic confusion, fear of attacks on aid convoys and the collapse of local authority is also making it difficult for help to reach quake victims.
On Monday, hundreds of people lined up outside the American and Canadian embassies in hopes of getting a visa to leave the country.
Others struggled to board buses and leave the capital.
Livena Livel, a 22-year-old mother was heading out of town to her father's home - a four-hour drive from Port-au-Prince. Livel says that she and her one-year-old daughter, along with six other relatives, have scraped together their last money to pay for the trip.
The $8 one-way ticket, amounts to about three days income for most Haitians.
The U.S. military sent more troops to Haiti on Monday to help with security and the distribution of food and water.
General Ken Keen, who is commanding U.S. military relief operations in Haiti, says logistical obstacles to aid delivery are being overcome.
"Every day, we increase our capabilities to reach out [to Haitians in need]," he said. U.S. helicopters are at work in Haiti, ferrying food and water to distribution points in and around the devastated capital, where three-million people struggle to survive.
General Keen says U.S. troops are working to assume more responsibility for aid distribution, which will allow U.N. peacekeepers in Haiti to focus on security concerns.
U.N. Secretary-General Ban Ki-moon has asked the Security Council to boost the U.N. stabilization mission in Haiti by 3,500 troops and police officers, who would join 9,000 security personnel already there.
Alain Le Roy, the U.N. 's peacekeeping chief - Under-Secretary-General for Peacekeeping Operations - says that it is important that aid convoys reach those in need quickly. "Of course there are incidents here and there, sporadic incidents here and there, mostly due to frustration for not getting food and water quickly enough," he said. "And, it's very important that the humanitarian convoys can reach very rapidly the people otherwise we will have security problems." World leaders have promised massive amounts of assistance to rebuild the capital and international aid pledges for Haiti continue to grow.
The European Union offered more than $500 million in assistance and hundreds of millions more have been pledged by the United States and other nations.
Last week's earthquake damaged Port-au-Prince's airport and seaport. U.S. military officials say a rescue and salvage vessel arrived Monday that will be used to send down divers to assess what may be blocking channels in the port as well as possible places to unload cargo.
