Battle of Chillianwala
In the Second Anglo-Sikh War, Lord Gough attacked a Sikh army under Raja Sher Singh in thick jungle near the Jhelum. The British took heavy losses and fell back, and although Gough claimed a win, the result brought an outcry in Britain.
The war had grown out of the rising at Multan in April 1848. Raja Sher Singh joined it that September, and the two armies met first at Ramnagar in November. On 13 January 1849, Sikh guns opened on the British as they prepared to camp, and Gough ordered an attack at once.
The jungle broke up the British formations, and their cavalry and guns gave little help. Sikh gunners routed Brigadier Pennycuick's brigade and Sikh horsemen broke the British cavalry line. After about three hours Gough ordered a general withdrawal.
The Encyclopaedia of Sikhism gives British losses as 2,446 men and 132 officers killed, and four guns. These look like total casualties rather than deaths: Wikipedia's summary gives 602 killed, 1,651 wounded and 104 missing, with 4,000 to 8,000 Sikh losses. The same two sources differ on Sikh strength, at 12,000 and 10,000, and the entry says British despatches overstated it.
Lord Dalhousie mocked Gough's claim of victory, and the decision was taken to replace him with Sir Charles Napier. Multan surrendered on 22 January, before the change could take effect.[EoS][Web]