The exchange twice temporarily halted trading on the FTSE small cap index before resolving the issue in the early afternoon.No explanation for the outages has been provided but FTSE 100, FTSE 250 and International Order Book securities were not affected.This is the third day of trading disruption for the LSE in two months: trading in small cap stocks was down for more than an hour in October, while the FTSE Russell indexes were affected by an outage last month.