Floods triggered by monsoon rains have crippled Pakistan's biggest city and commercial hub of Karachi. As a result the government has again came under pressure to provide relief for about 300,000 people left homeless by floods in the south. The heavy downpour has paralysed the city making it difficult for the locals to carry out day-to-day activities. Pakistan, regarded as one of the world's most unstable countries, is haunted by memories of epic floods last year, which brought widespread criticism of the government because of its slow response.