US grocery retailer Kroger has reported lower quarterly profit as it struggled with higher operating costs and fierce competition from US retail giant Wal-Mart. The Cincinnati-based company reported a profit of US$190.4m, or 25 cents a share, for the second quarter to 16 August, compared to $264.0m, or 33 cents a share, a year earlier. Analysts had been expecting, on average, profit of 32 cents a share.