BOGOTA, Colombia (Reuters) -- Colombia faced its most serious
                   political crisis in years Thursday as government opponents slammed plans
                   to shut down Congress because of a corruption scandal in which they say
                   President Andres Pastrana shares much of the blame.

                   The heated atmosphere was reminiscent of the 1996 scandal over charges
                   Pastrana's predecessor, Ernesto Samper, used Cali cartel cocaine money to
                   bankroll his campaign. Some veteran political observers believe Pastrana could
                   lose his job over the latest scandal.

                   It erupted two weeks ago when the government launched a probe into more than
                   550 shady contracts, worth millions of dollars, that were endorsed by the House
                   of Representatives -- including one worth about $49,000 to build a new toilet.
                   Another contract, worth $56,990 and awarded just before the clock struck
                   midnight on New Year's Eve, was ostensibly signed to iron out millennium bug
                   problems in the House.

                   Independent lawmakers, meanwhile, have reported an alleged $3.6 million scam
                   in the Senate involving the theft of office furniture, official vehicles and funds
                   from public coffers.

                   Critics say the government investigation has backfired and left Pastrana on
                   political quicksand, since most of the unbudgeted money funneled into Congress
                   was approved by the finance ministry and allegedly used to curry political favors.

                   That, in turn, has awakened widespread suspicions that a planned referendum in
                   July, in which voters would be asked if they support revoking the current
                   mandate of Congress, is a smokescreen to cover up the country's pork barrel
                   politics.

                   The watchword of Pastrana's campaign was "change," and he repeatedly vowed
                   to root out the corrupt practices that have long corroded the highest levels of
                   government. He has, until now, relied on dissident members of the main
                   opposition Liberal Party who back his ruling coalition to push key legislation
                   through Congress.

                   Liberals, with a majority in Congress, have led the charge against Pastrana since
                   he proposed shutting it down as part of a "war against the corrupt" in a surprise
                   national address Tuesday night.

                   "They're playing with fire," former President Alfonso Lopez said Thursday,
                   when asked about the referendum which must still be approved by Congress.

                   "This is the result of the system President Pastrana's government adopted from
                   the start, in which it has built an artificial majority (in Congress) through payouts
                   made to Liberals willing to join the ranks of the government," he said.

                   Many politicians have hailed Pastrana's bid to dissolve Congress and hold
                   elections for new lawmakers in October. But Lopez, who called the government
                   weak and increasingly unpopular, dismissed it as "a political game" aimed only at
                   boosting support for the troubled Pastrana, whose handling of the economy and
                   peace talks with Marxist rebels have been widely criticized.

                   "It's not impossible," the Liberal Party's elder statesman added in one of several
                   interviews with local media, when asked if the referendum might force Pastrana
                   to leave office.