Bomb found before senator's visit: ; U.S. officials downplay significance of incident

BOGOTA, Colombia - Police discovered a roadside bomb outside atown hours before a U.S. senator and U.S. ambassador were to visit,a Colombian police commander said today. Sen. Paul Wellstone, D-Minn., and U.S. Ambassador Anne Patterson were the likely targets,Police Col. Jose Miguel Villar said.

But a State Department official in Washington said Patterson tolddepartment officials by telephone that she did not see it as anassassination attempt. Another State Department official, alsoasking for anonymity, added that it is not unusual for such devicesto be found in Barrancabermeja, considering the town's reputationfor violence.

Hours before the two U.S. officials flew into Barrancabermeja onThursday, police discovered two shrapnel-wrapped land minesalongside the road leading from the airport to the town and arresteda suspected rebel, Villar said.

The land mines each carried a 6.6-pound explosive charge, wereattached to cables and a detonator and were ready to be set off,Villar said in a phone interview from Barrancabermeja, 155 milesnorth of Bogota, the capital.

Bernardo Alvarez Duarte, a suspected member of the rebel NationalLiberation Army, or ELN, was arrested at the site, Villar said.

"If the bomb had gone off, it could have caused immense damage,"Villar said. "It would have spread shrapnel over a wide area andcould have taken out 10 or 15 people."

Patterson said she had received sketchy reports about the bomb asthe delegation departed Barrancabermeja.

Many residents of Barrancabermeja had known the U.S. delegationwas going to arrive. But security forces had kept confidential plansto transfer the party from the airport to the town by helicopter.Even if the bombs had exploded, the delegation would not have goneanywhere near them.

Villar said the Americans were probably the target of the bomb,but he could not absolutely confirm it. Alvarez, the arrested man,was being questioned for further information.

Washington supports the Colombian military in its fight againstthe ELN and a bigger rebel group, the Revolutionary Armed Forces ofColombia, or FARC.