A group of Greenpeace activists held a protest outside Chevron Corp.'s offices here Friday to draw attention to an oil spill off Brazil's southeastern coast.

The demonstrators dressed in orange Chevron oil-worker uniforms with black ink stains poured black-colored paint from two barrels bearing the company's name on the pavement to symbolize the spill.

They also held up signs in both English and Portuguese with the message: "Chevron: Your Mess, Our Problem."

The spill occurred 10 days ago at a Chevron-operated appraisal well in the vicinity of the oil supermajor's offshore Frade field, located 370 kilometers (230 miles) from the coast of Rio de Janeiro state at water depths of approximately 1,200 meters (3,930 feet) in the Campos basin, Brazil's main oil-producing area.

On Thursday, the San Ramon, California-based company said in a statement that it was cementing the deep-water well and had confirmed that "there has never been any oil flow from the wellhead and current monitoring indicates oil from nearby seep lines on the ocean floor has been reduced to infrequent droplets."

The company added that the oil sheen had "substantially dissipated" and estimated the volume of crude on the ocean surface at less than 65 barrels.

According to Chevron, the sheen "is located about 120 kilometers (74 miles) offshore and continues to move in a southeasterly direction away from the Brazilian coast."

The company had earlier estimated the amount of oil spilled at between 400-650 barrels, while other reports cited by the official Agencia Brasil news agency put the volume at as much as 2,300 barrels.

Activist Leandra Goncalves accused Chevron of minimizing the problem and estimated that the oil sheen could extend over an area greater than 160 sq. kilometers (62 sq. miles).

"It's surprising that the company has not offered to take the media and civil society organizations to the site of the mishap and has only published vague press releases about what's happening ... So much secrecy is a sign that Chevron does not have an adequate safety plan," Goncalves said in a statement.

Chevron said that it was continuing to "coordinate and deploy resources to monitor and manage the remaining sheen" and that a fleet of 18 vessels was being used in those efforts.

The company noted that full production activities have been maintained at Frade throughout the "seep incident," adding that daily output at the project, which it began drilling in 2009, amounts to approximately 79,000 barrels of oil equivalent.

But it said "all development well drilling" in the field has been suspended.

Brazil's president, Dilma Rousseff, has ordered a "rigorous investigation" into the spill.

With a 51.7 stake, Chevron is the lead operator in the Frade field. Brazilian state oil giant Petrobras holds 30 percent of the venture and the rest belongs to the Frade Japao Petroleo Ltda. consortium.