BOGOTA (Reuters) - Colombian state-run oil company Ecopetrol has halted pumping on the country’s No. 2 oil pipeline after a rebel bombing that sent crude spilling into a nearby river, a source at the company told Reuters on Friday.

The attack on the 485-mile (780 km) Cano-Limon Covenas pipeline caused a spill in Arauca province’s Bojaba river, near the border with Venezuela, Ecopetrol said in a statement.

Clean-up crews were working to contain the spill, the company said, which so far was several kilometers away from drinking water sources.

President Juan Manuel Santos blamed the leftist National Liberation Army (ELN) rebel group for the attack.

The government and the ELN announced in March they would soon begin formal peace talks in Ecuador, after over two years of preliminary negotiations.

“It’s inconceivable that this group, instead of giving concrete displays of peace, insists on kidnapping and attacking the infrastructure of Colombians, like it did today with another pipeline bombing, causing immense harm to the environment,” Santos said in televised remarks.

The president will travel to Arauca on Saturday to meet with security officials.

Cano-Limon has the capacity to transport up to 210,000 barrels of crude daily from oil fields operated by U.S.-based Occidental Petroleum, near the border with Venezuela, to the Caribbean port of Covenas.

Attacks by the ELN on oil installations have been a frequent occurrence during a conflict that has taken more than 220,000 lives and displaced millions over the past 52 years.