Set-top box maker Pace is racing ahead, surging 8% on Wednesday afternoon, which Centamin is still on shaky ground.Egypt-based miner Centamin is the highest faller as the crisis in the nation escalates. Yesterday, shares rallied after the group issued a reassuring statement over the impact of the current unrest in the country. Today's events have taken their toll on the company, with shares falling over 6%.Peruvian silver miner Hochschild is higher after publishing positive drill results from the early stage Pariguanas project, part of its joint venture agreement with Buenaventura.Big news on the market today is JD Sports confirming its offer for struggling rival JJB Sports, though its noted that discussion are at a very early stage. JD is making moderate gains."There can be no certainty that an offer will be made by JD Sports Fashion for JJB Sports, nor as to the terms on which any offer might be made," it said.FTSE 250 - RisersPace (PIC) 208.10p +7.88%CSR (CSR) 405.00p +3.93%Hochschild Mining (HOC) 510.00p +3.74%Aquarius Platinum Ltd. (AQP) 374.90p +3.71%Northumbrian Water Group (NWG) 306.00p +3.38%Salamander Energy (SMDR) 302.80p +3.34%Supergroup (SGP) 1,590.00p +3.25%Ashtead Group (AHT) 178.10p +2.95%Afren (AFR) 154.90p +2.92%Hikma Pharmaceuticals (HIK) 858.50p +2.88%FTSE 250 - FallersCentamin Egypt Ltd. (CEY) 137.50p -6.46%Cookson Group (CKSN) 652.00p -5.09%Spectris (SXS) 1,345.00p -4.00%Unite Group (UTG) 203.00p -3.06%Paragon Group Of Companies (PAG) 184.20p -3.05%Charter International (CHTR) 786.50p -3.02%St. Modwen Properties (SMP) 168.80p -2.88%Morgan Crucible Co (MGCR) 263.60p -2.80%Kenmare Resources (KMR) 37.75p -2.71%Chemring Group (CHG) 3,376.00p -2.65%