Egypt-focused gold mining company Centamin saw shares tumble early on after saying that it has suspended operations at its Sukari mine due to issues with fuel suppliers and delays with gold exports. Canaccord Genuity downgraded the stock to 'hold' this morning and slashed its target price from 110p to 40p. Centamin said that it has received an "illegal" $65m retrospective claim from a local fuel company, which is now refusing to supply more fuel to Sukari until the claim is paid. In addition, the firm also announced that its process of gold exports has been hit by delays due to "an unforeseen and arbitrary request from customs officials" for the prior approval from authorities. High Street retailer Sports Direct fell despite delivering significant growth across the board in the first with with revenue up 22.5%. Bus and train group National Express gained after saying it is on target to deliver full-year results in line with company expectations despite challenging conditions. SuperGroup, the owner of clothing retail brand SuperDry, was a strong performer, rebounding after a heavy fall yesterday. The company revealed on Wednesday a 31.5% fall in first-half reported profit before tax.FTSE 250 - RisersRuspetro (RPO) 89.20p +6.19%Supergroup (SGP) 591.00p +6.10%Man Group (EMG) 81.50p +5.03%National Express Group (NEX) 187.40p +4.00%Homeserve (HSV) 237.70p +3.12%Michael Page International (MPI) 389.00p +3.05%Ashtead Group (AHT) 401.70p +2.74%NMC Health (NMC) 181.00p +2.61%3i Group (III) 216.80p +2.31%Savills (SVS) 459.80p +2.31%FTSE 250 - FallersCentamin (DI) (CEY) 27.41p -47.99%Sports Direct International (SPD) 382.70p -6.50%Imagination Technologies Group (IMG) 406.60p -4.33%Kenmare Resources (KMR) 30.03p -3.66%Dechra Pharmaceuticals (DPH) 613.00p -3.62%Home Retail Group (HOME) 124.20p -3.50%Restaurant Group (RTN) 374.00p -3.21%Petropavlovsk (POG) 330.30p -2.97%New World Resources A Shares (NWR) 269.00p -2.89%Ocado Group (OCDO) 76.20p -2.31%FTSE TechMARK - RisersKofax (KFX) 293.50p +2.98%Phytopharm (PYM) 9.38p +1.35%Torotrak (TRK) 28.00p +0.90%Skyepharma (SKP) 70.00p +0.72%Xaar (XAR) 288.00p +0.70%E2V Technologies (E2V) 114.50p +0.44%Corin Group (CRG) 69.75p +0.36%Phoenix IT Group (PNX) 177.50p +0.28%Sepura (SEPU) 95.50p +0.13%Innovation Group (TIG) 23.50p 0.00%FTSE TechMARK - FallersAntisoma (ASM) 1.60p -10.11%Emblaze Ltd. (BLZ) 44.50p -4.30%Optos (OPTS) 162.00p -3.57%Filtronic (FTC) 36.00p -2.70%NCC Group (NCC) 860.00p -1.99%XP Power Ltd. (DI) (XPP) 1,001.00p -1.86%BATM Advanced Communications Ltd. (BVC) 17.00p -1.45%Vectura Group (VEC) 85.00p -1.16%Ricardo (RCDO) 368.25p -0.47%Consort Medical (CSRT) 799.00p -0.12%