The decision to curb P-Notes has not gone down well with the markets with the benchmark index hitting the lower circuit breaker in opening moves. The Sensex 7.9 per cent or 1,507 points to 17,544 levels. As a result, the trading has been haled for an hour. In the broader markets, the Nifty skidded 9.25 per cent or 524 points to hit a low of 5,143 levels.