The Crown Prosecution Service says there was "insufficient evidence" to charge two former zoo keepers at Twycross Zoo under the Animal Welfare Act.
Three people were arrested by Leicestershire Police after reports two elephants were mistreated at the Zoo. A file was passed to the CPS relating to two of those arrested. No further action was taken against the third.
CPS East Midlands has examined evidence presented to us by Leicestershire Police in relation to allegations of mistreatment of elephants at Twycross Zoo.
"This has been examined in detail and we have informed Leicestershire Police that there is insufficient evidence for a realistic prospect of conviction, in that the conduct shown is not sufficient to prove a criminal offence under the Animal Welfare Act 2006."
The elephants suffered no lasting ill effects."
Two former zoo keepers will not face any further action over claims they mistreated two elephants at Twycross Zoo.
Three workers were dismissed and then arrested by Leicestershire Police in connection with mistreating the animals later year.
The Crown Prosecution Service say there was insufficient evidence to prove a criminal offence.
Two snow leopards will go on full view to the public at Twycross Zoo for the first time.
The brothers were born on 1 May and have been settling down in an off-show area with their mother, Irma.
Cameras placed in an off-show den allowed zoo staff and vets to watch the births live, and keep a close eye on the cubs without disturbing the new mother.
A decision is expected over the next few days as to whether two former zookeepers should be charged with mistreating elephants at Twycross Zoo.
Three members of staff were dismissed and arrested in connection with mistreating the animals after the zoo reported its concerns to Leicestershire Police last year.
The elephants suffered no lasting ill effects.
"We've had evidence from Leicestershire Police about two of the people but a decision was taken some time ago against the third, determining no further action.
"A decision on whether to charge anyone in connection with the investigation would be taken in a matter of days."
Twycross Zoo's group of chimpanzees who made their way into an area of the zoo they should not have been in were offered ice cream and fizzy drinks as a bargaining tool.
Zookeepers at the Leicestershire zoo had to coax the animals out of the secure area this morning by offering them the sweet treats, which left them "a little excited."
The zoo was closed for less than two hours due to "safety procedures", but "no people or chimps were harmed during the incident".
Staff at Twycross Zoo have revealed how they tempted a group of straying chimpanzees back into their correct living areas:
Keepers encouraged the chimps back into their normal living areas with ice cream and fizzy drinks.
The zoo reopened at 11.30am today and all of the chimps are fine, if not a little excited about having ice cream for breakfast.
Twycross Zoo was closed to the public after "some chimpanzees" got into an area where they should not have been.
A spokeswoman for Leicestershire Police said: "A call came in at 9.35am from the zoo to let us know that some chimpanzees, that were in the process of being moved from one building to another.
"In the process of this they have perhaps gone into an area of that building that they shouldn't have been in.
"They don't appear to have actually physically escaped. As a precaution, we've been called by the zoo."
The spokeswoman said they stopped people going into the park for a "short time", and added that there was no danger to anyone in the park and no animals were on the loose.
Twycross Zoo has re-opened following an 'animal incident'. It has not be confirmed what animal was involved.