He set a trap using a cage baited with a sheep's head.
"We understand the concerns of local communities in both Bristol and London and officers will remain in the Clifton and Shepherd's Bush areas over the coming days to reassure those affected by this tragic incident," he added."Anyone with any concerns is encouraged to speak with them."
The Met Police had previously put out a statement saying they wanted to speak to a Yostin Andres Mosquera.Police are not looking for anyone else and the man arrested at Temple Meads Station is being taken to London for questioning.Just before midnight on Wednesday, Avon and Somerset Police received a report of a man with a suitcase acting suspiciously on the Clifton Suspension Bridge.
Officers arrived within 10 minutes, but the man had left, leaving the cases behind. A second suitcase was found nearby.The Metropolitan Police took over the investigation after body parts were found in the flat west London flat.
Police have said formal identification of the two victims is yet to take place.
A 36-year-old man who was arrested in Greenwich in south-east London on Friday in connection with the investigation has since been released without charge.The gas released during the process is also collected for energy use.
Elsewhere, nearly 50,000 tonnes of garden waste was recovered for composting at three sites around the county.The remaining 42% of household waste was sent for energy recovery, which usually involves waste being incinerated to generate electricity.
Overnight snow has led to disruption in parts of Lincolnshire with some schools closed and reports of weather-related crashes.The Met Office issued a yellow weather warning for "a spell of snow" in the region from 19:00 GMT on Monday until 10:00 on Tuesday.