Salmonella infection is a leading cause of morbidity and mortality worldwide. Because contamination of food and water by pathogens is sporadic, fecal indicators are used to determine the microbial quality of food and water. One of these important indicators is E. coli which shares physiological and ecological features with Salmonella. However, culture-based methods for detection of these organisms require enrichment, plating on selective and differential media followed by chemical and serological testing. Altogether this can take several days to complete. Moreover, molecular-based methods of detection are limited by the fact that many of these cannot distinguish between viable and non-viable organisms. A need exists for rapid, specific and sensitive diagnostic assays for the detection of bacterial pathogens to enhance food safety and to ensure appropriate clinical interventions. To address this need a method was developed that combines phage amplification within target bacteria with molecular detection of a sequence characteristic of the phage using Loop Mediated Isothermal Amplification (LAMP). For the detection of S. Newport, the broad host range T4-like Salmonella phage vB_SnwM_CGG4-1 was isolated, characterised and sequenced using S. Newport as the host. This phage was able to infect all 28 serovars against which it was screened, including non-typhoidal and typhoidal Salmonella. Phage T4 was employed for the E. coli detection assay. The LAMP reaction was either followed in real time using the Bioluminescent Assay in Real Time (BART-LAMP) or was analysed by endpoint colourimetric detection of pyrophosphate with ammonium molybdate as the chromophore. The assay was able to detect around 5 CFU/ml of Salmonella Newport and 10 CFU/ml of E. coli B within 8 hours. This prototype detection assay can be adapted for the detection of various bacterial pathogens in food, water and clinical samples.