Updated

Former President Jimmy Carter renewed efforts to mediate Venezuela's political crisis Monday even as violence surged again between supporters and opponents of President Hugo Chavez. Gunfire during a protest march left one dead and 15 wounded, officials said.

Miranda state Gov. Enrique Mendoza, a Chavez opponent, said Chavez supporters attacked an opposition march in Charallave, about 20 miles south of Caracas, on the 50th day of a strike against Chavez.

Raul Gonzalez, 38, said he and other Chavez supporters blocked a road as opposition marchers approached and both sides began tossing rocks and bottles.

"I heard shots and fell down," Gonzalez said at Hospital General de Ocumare del Tuy, where he was being treated for a bullet wound in his leg. "There were shots from all over. Everything was in confusion."

Gonzalez said he did not know where the gunfire came from.

Opposition marcher Mayordina Morales, 52, said both sides were throwing objects at each other when police started shooting.

The shooting victim was identified by officials as Carlos Garcia, who is about 30 years old.

Fifteen people were wounded gunfire, said Milagros Toro, an official with the state epidemiology department. Twelve people suffered other injuries.

Six people have died in protests since Venezuela's opposition called the strike Dec. 2, crippling the world's fifth-largest oil exporter.

Carter was meeting with Chavez, opposition figures and Cesar Gaviria, secretary general of the Organization of American States. Gaviria has tried since November to mediate an electoral solution to Venezuela's crisis. Carter was participating in a negotiating session Monday.

"I have always hoped for a resolution, and I hope there will be one," said the Nobel Peace Prize winner, whose Atlanta-based Carter Center is sponsoring the talks with the OAS and the United Nations.

Chavez has threatened to abandon the talks. On Sunday, he accused the opposition of trying to oust him even as its leaders sat at the negotiating table.

"We don't talk with terrorists," Chavez said.

Opposition parties, business leaders and labor unions called the strike to demand that Chavez resign or call early elections. The National Elections Council accepted an opposition petition and agreed to organize a Feb. 2 nonbinding referendum asking citizens whether Chavez should step down.

Chavez says the constitution only allows a binding referendum halfway through his six-year-term, or August. The Supreme Court is considering the matter.

The strike has slashed Venezuela's oil production by more than two-thirds and caused severe shortages of gasoline, food and drinking water. It has cost Venezuela $4 billion, according to the government, and contributed to the plummeting of the bolivar currency.

Six countries -- Brazil, Chile, Mexico, Portugal, Spain and the United States -- began an initiative called "Friends of Venezuela" to help end the crisis. Chavez warned the six nations his government will not allow interference in domestic affairs.

Trying to break the strike, Chavez sent soldiers to seize water, soft drinks and beer from two bottling plants, provoking an outcry from business leaders, human rights groups and U.S. Ambassador Charles Shapiro.

One bottler was a Coca-Cola affiliate while the other belonged to Venezuela's largest food and drinks producer, Empresas Polar. Both firms denied hoarding goods.

The Venezuelan American Chamber of Commerce condemned the raids as "a grave rupture of the state of law." It warned more than 1,000 affiliates that the army could commit more abuses and urged them to report alleged violations.

Microsoft Corp. said Monday it was shutting down two Venezuela offices because it cannot guarantee employees' security. The company has about 85 employees in Caracas and six in Maracaibo.

Chavez has used troops to seize gasoline trucks, arrest striking oil tanker crews and keep strikers out of oil installations. He has fired more than 1,000 employees from the state oil monopoly.

Before the strike, Venezuela was the world's fifth-largest oil exporter and fourth-largest oil supplier to the United States.

It pre-strike output of 3 million barrels a day was at 800,000 barrels, the government claims. Strike leaders put the figure at 627,000.

The 48-year-old Chavez was elected in 1998 and re-elected in 2000 on promises to redistribute the country's vast oil wealth among the poor majority.

His opponents say his leftist policies have driven the country toward economic ruin, citing 17 percent unemployment and 30 percent inflation. They also say his autocratic style erodes democratic institutions.

The government Monday also notified private television stations Globovision and Radio Caracas Television that they faced administrative proceedings for allegedly supporting efforts to topple Chavez.

The complaint alleges the stations illegally ran opposition advertisements supporting the 50-day-old strike and promoting anti-government marches, Globovision reported.

The stations, which long have accused Chavez of trying to stifle freedom of expression, face fines or the losses of their broadcasting licenses.