* Interim president attempting to restore order
* Seleka fighters say will back Samba-Panza
* Heavy weapons fire in northwest of country
* Displaced residents say too afraid to go home
* Sectarian violence has killed more than 2,000
By Paul-Marin Ngoupana and Emmanuel Braun
BANGUI, Jan 21 (Reuters) - Central African Republic's new interim president said on Tuesday she would hold talks with armed groups in an effort to restore order to the former French colony, where at least seven more people were killed in sectarian violence in the north.
In a sign of the growing support for Catherine Samba-Panza, the mayor of Bangui appointed as interim president on Monday, a representative of former Seleka rebels, who seized power in a coup last March, gave her his backing.
Samba-Panza replaced former Seleka leader Michel Djotodia, who stepped down on Jan. 10 under international pressure for failing to stop months of killings that have pitted Seleka's mostly Muslim fighters against anti-balaka militia drawn from the Christian majority.
The violence has driven more than 1 million people, or about a quarter of the population, from their homes. The United Nations says more than 2,000 people have been killed.
"I want to meet with the armed groups and listen to them," Samba-Panza told reporters on Tuesday. "If they took up arms, then there is a reason for that."
General Ousmane Mamadou Ousmane, president of the commission in charge of military reform of the Seleka alliance, said: "Our goal is clear, to support the new president to finish her mission, to support her so that peace returns to Central African Republic."
A spokesman for a major group of anti-balaka fighters said on Monday he believed the new president could end violence.
On Tuesday, at least seven people were killed near the town of Bang, close to the borders with Chad and Cameroon, according to resident Jerome Kossine, who spoke to Reuters from a hiding place in the bush.
"Everything began with an attack by anti-balaka who killed a Seleka member early this morning in Bang," he said. "Then the Seleka based there came out in revenge and caused panic among the population by pillaging and burning houses."
Light and heavy weapons fire rang out from the area throughout the morning, he said. A second resident in nearby Ngaoundaye said Seleka fighters went from house to house, stealing from inhabitants and attacking them.
Concern over violence in the mineral-rich nation of 4.6 million people has prompted greater international involvement. The European Union has agreed to send 500 troops to support a 1,600-strong French mission, named Sangaris after a local butterfly.
A senior U.N. official has warned of the risk of genocide.
Samba-Panza used her first news conference as president to appeal to the international community to step up aid to help relaunch government activities, which have ground to a halt due to lack of money. Civil servants have not been paid in weeks.
Residents in a makeshift camp housing 100,000 at Bangui's international airport also welcomed the appointment of the new president but said they still feared attacks.
"We can't return home," said Richard Prince Masengue, referring to his neighbourhood. "The Sangaris operation has not arrived yet so there is still insecurity there."
Aid workers could struggle to feed the displaced after a strike by U.N. truck drivers in neighbouring Cameroon who say it is too dangerous to enter the country, leaving 1,500 tonnes of food, enough to feed 155,000 people for a month, stranded at the border.
"Our stocks are almost finished here, and within the next few days we'll have nothing left to distribute," WFP spokesperson Alexis Masciarelli told Reuters, saying it was considering an airlift to bring in emergency supplies. (Additional reporting by Emmanuel Braun in Bangui and Misha Hussain in Dakar; Writing by Emma Farge; Editing by Daniel Flynn and Janet Lawrence)