A mass protest in Hamburg against West German opposition leader Franz Josef Strauss became violent late Monday, resulting in injuries to 102 police officers and four demonstrators, authorities announced yesterday.

The violence underscores the political tension in West Germany as Strauss steps up his campaign to oust Chancellor Helmut Schmidt in the October election, Washington Post Bonn correspondent Bradley Graham reported. Strauss' candidacy has aroused fierce opposition among West Germany's leftist groups, which police said were responsible for the violence. gThey consider the conservative Bavarian state premier a threat to personal freedoms and to East-West detente.

The clashes appeared to confirm the fears of West German authorities that anti-Strauss sentiment, fanned lately by Schmidt's Social Democratic Party, will boil over as the campaign heats up.

The trouble began after police sealed off the meeting hall where Strauss was speaking to about 6,000 supporters. Outside, militants among what had been a peaceful crowd of about 15,000 charged the police line, according to the police.

Fighting broke out and some cars were damaged or set afire. Fire trucks sent to the scene were surrounded by demonstrators and damaged. Police finally used tear gas to disperse the crowd.