Three dogs were killed and two poisoned by meat left in a park laced with insecticide Methomyl, police said.
Police have renewed appeals for information after the two bull lurches and springer spaniels ingested the toxic meat left in Fryent Country Park in Brent, north-west London, last month.
The substance was analysed by experts who discovered it was Methomyl – a carbamate insecticide which is banned in the UK due to its toxicity.
Last month dog owners reported their pets to be ill within hours of ingesting the meat left on grass verges in Salmon Street in March.
Lesley Hastings, 53, told the Standard how both her lurcher Toby and shih tzu-Jack Russell cross Maisy picked up the dumped food while making her way home from the park. Toby was killed after eating the meat.
Police officers are warning dog walkers in the area to be extra vigilant and to wear gloves if handling anything which could be contaminated. There are also extra officers patrolling the park.
RSPCA chief inspector, Simon Osborne, said: “This kind of poison is extremely toxic for dogs and other animals if consumed and it is very concerning to hear that this is what caused the recent deaths.
"We urge anyone who knows of any person who has a stock of this particular insecticide at home or in even their shed or garage to talk the Police or ourselves in complete confidence, so we can investigate further."
Sergeant Peter Rowntree, of Brent Police, said: “I am grateful to everyone who has assisted to raise awareness regarding these incidents and I would encourage all dog walkers and the users of any of our parks, to be vigilant and phone through any suspicious activity.
“With better weather and longer hours of daylight the parks will be busier and I am hopeful that any criminal activity is more likely to be seen and phoned through to us.”
A Natural England spokesperson said: “It’s distressing and disturbing to think that somebody could be using such a dangerous toxin so indiscriminately. We would encourage anybody with any information on these incidents to contact Brent Police immediately.”
Anyone with information can call 101 or Brent Council, Animal Welfare on 020 8937 5256.
