UNITED NATIONS -- All UN flights to Haiti have been suspended after commercial jetliners were struck by gunfire and violence worsened in the country, a UN spokesperson said Tuesday.

A commercial flight of US Spirit Airlines was shot at by gunfire when it was approaching the Haitian capital of Port-au-Prince on Monday, which forced it to be diverted to the neighboring Dominican Republic. A flight attendant was injured.

On the same day, a JetBlue Airways flight returning from Port-au-Prince was found with bullet damage after arriving in New York.

According to the UN partners, armed groups took to the streets in the capital, with at least 20 armed clashes reported and several roadblocks erected, limiting movement across the city, Stephane Dujarric, spokesperson for the UN chief, told reporters.

The Toussaint Louverture International Airport in Port-au-Prince has been closed until Nov. 18. The port remains open from the sea, but road access to the port is currently not possible, he added.

At a result, all UN flights have been suspended, limiting the flow of humanitarian staff and resources, the UN spokesperson said. The delivery of 20 trucks of food and medical supplies to the south was also postponed.

The Office for the Coordination of Humanitarian Affairs warned that escalating violence is worsening an already dire humanitarian situation.

The UN partners reported that all schools in the Haitian capital have been closed. Additionally, operations providing cash assistance to 1,000 people had to be canceled amid the ongoing violence.

Dujarric called for an end to the escalating violence, to allow for safe, sustained and unimpeded humanitarian access, as well as the protection of people.