Tensions continue at a high level at Grupo Mexico’s largest copper mine in Cananea, in Mexico’s Sonora state.

Workers represented by the Mexican National Union of Mine, Metal and Allied Workers (SNTMMSRM) have been on strike against the huge facility since last summer. On Jan. 11, a labor arbitration board declared the strike illegal because of technicalities, and federal and state authorities moved in with lightning speed, seizing the mine and delivering it to the Grupo Mexico management. However, strikers did not give up and appealed the board’s decision to the courts, while entering negotiations with management, which have not been fruitful so far.

This led to a strange February ruling by a federal judge, namely that the strike was legal after all but that union members who wanted to should be allowed to return to work. This ruling conflicts with normal Mexican labor law, under which scabs are not supposed to be let in when a legal strike is in progress.

Both union and management spokespeople expressed astonishment at the ruling, which the union pointed out set the stage for possible violent confrontations between strikers and strikebreakers.

Grupo Mexico, evidently unable to get enough union members to cross the picket lines to run the mine, has now started to recruit temporary workers (strikebreakers) who never were members of the union, in violation of the judicial decree. The union’s leadership has sworn not to allow any such temporary workers to enter the mine. This already has led to some physical confrontations, and burning of the automobiles of some union activists. Grupo Mexico’s management blames the union leadership for the violence, and also for what they claim is damage to company property during the time the strikers controlled the facility, and is calling for arrests and prosecutions.

Complicating the situation is the question of the status of the Mine and Metal Workers Union’s secretary general, Napoleon Gomez Urrutia, who is living in exile in Vancouver, B.C., Canada. Two years ago, the Mexican government tried to prosecute Gomez for supposed corruption and violations of labor law, based on complaints by a small group of union dissidents. Gomez and the union leadership, strongly supported by Mexico’s National Workers’ Union federation and the U.S. AFL-CIO and United Steelworkers Union, claim the accusations are false and politically motivated. The government has been unwilling to give Gomez assurances that he can return to Mexico without facing arrest.

Union leadership elections are scheduled for May 2. The union’s secretary for political affairs, Carlos Pavon, accused the Grupo Mexico management of spending millions of dollars to set up offices in communities where the union has members, to persuade workers to leave the union and thus undermine the election in which Gomez Urrutia is likely to be re-elected.

Labor activists in Mexico and beyond are watching the situation at Cananea carefully. Mexico’s right wing president, Felipe Calderon, of the pro-business National Action Party, is demanding “liberalization” of Mexican labor law, which basically means strengthening the hand of business and weakening the unions. So far, the workers at Cananea have expressed strong suspicions of pro-management partisanship on the part of Calderon’s Secretary of Labor and Social Welfare, Javier Lozano Alarcon. What happens with the Cananea mine and the union elections will show how far those suspicions are justified