Assange denies both allegations.
Assange's lawyers meanwhile confirmed that USA prosecutors have 65 days to submit a full set of charges, raising the prospect of additional criminal allegations being introduced that would result in a far longer sentence.
WikiLeaks co-founder Assange was arrested on Thursday in relation to an extradition request from the USA, where he is facing computer hacking charges.
Julian Assange's mother has taken to Twitter to call on authorities to be gentle with her son, who's jailed in London after his removal from the Ecuadorian Embassy.
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"We do not presume guilt, of course, but we believe due process should be followed and the complainant should see justice be done", the letter says.
"It is therefore of grave concern to us that it appears that the Swedish authorities were not aware of the plans made to arrest Mr Assange yesterday in London, and we would welcome clarity as to what action the United Kingdom authorities took to ensure that the Swedish prosecutors were informed in advance of this decision", it adds.
He hired a team of American and British lawyers, who he hopes will keep him from being extradited to the United States, where he's wanted on hacking charges.
The 47-year-old Australian activist was arrested by British police on Thursday and forcibly removed from the Ecuadorian embassy in London after his asylum was revoked, bringing to an end more than six years in the building.
British politicians are free to lobby the government for a certain course of action, but it's up to the courts to decide whether the US request for Assange's extradition - and a possible future request from Sweden - should be honored.
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A legal source familiar with the case told AFP that Assange was being held at Belmarsh prison in southeast London.
Only last month, former USA intelligence analyst Chelsea Manning, previously imprisoned for downloading USA military and diplomatic documents for WikiLeaks in 2010, was again jailed for refusing to testify before a grand jury.
Ola Bini, who has lived in Ecuador for five years, was detained at Quito airport on Thursday as he prepared to board a flight to Japan, after the country's interior minister said three foreign citizens had been leaking private information related to the South American country.
After his dramatic arrest, Assange was taken to Westminster Magistrates' Court and found guilty of a British charge of breaching bail.
He could receive up to a year in prison when sentenced at an as yet undetermined later date.
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