Police raided a semi-detached house on a quiet residential street this morning.
Flashing blue lights were seen racing through Motspur Park before arriving in Stanley Avenue at about 10.30am.
Chris Bushe, who passed the house after the incident, said about seven people came out of the house but there was no sign of any arrests.
Four police cars were seen outside.
Merton police have yet to comment.
Did you witness the raid? Contact Louisa on 020 8722 6335, or email louisa.clarence@london.newsquest.co.uk.
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