were jain massacres in Tamil

Short answer: There is a well-known Tamil legend about mass killings of Jains in Madurai dating from the 7th–8th centuries, but it is considered by many scholars to be a legend rather than proven history. There are no contemporary Jain records of such a massacre, and the story first appears in Shaivite hagiographies later on. In Jain sources, this event is not documented as a factual historical massacre. The tale is often read as part of Shaivite-Samanar (Jain) rivalry in early Tamil literature, not as an established historical event. If you want the Jain perspective in brief: the legend is mentioned in later texts, but its historicity is doubtful and not supported by Jain inscriptions or early Jain writings.

Note: There can be different versions in Tamil Shaivite and Vaishnava traditions, and modern scholarship generally treats the episode as legendary rather than a confirmed historical massacre.

You can read more about this topic in the context of Jain heritage and Tamil history on relevant Jain-focused pages.