The daughter of an ex-Russian agent poisoned alongside her father in the UK "hasn't done anything to deserve" being targeted, a friend says.
Police are investigating the attempted murder of Yulia and Sergei Skripal after both were found unconscious in Salisbury, Wiltshire on Sunday.
Her childhood friend Irina Petrova told the BBC she remembered the Skripals as the "perfect family".
But she thought people might be afraid to speak publicly about the pair.
"I'm starting to get scared," she said. "No one wants to speak – even her relatives".
Ms Skripal, 33, and her 66-year-old father are being treated in hospital after being exposed to a nerve agent, nearly a week after being found slumped on a shopping centre bench in the city.
Home Secretary Amber Rudd is to chair a meeting of the government's emergency committee, Cobra, as the investigation into the attempted murder of the pair continues.
Security Minister Ben Wallace said it was "a very serious incident with horrendous outcomes" and the government was prepared to "respond with the full force of the UK's resources".
"Someone has come onto our soil… has recklessly, brazenly, committed what looks like a very nasty crime, with a nerve agent prohibited, by most international laws… and has potentially put lots of people at risk," he told the BBC Radio 4's Today programme.
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When asked if Mr Skripal worked for British intelligence services, he said it was a long-standing government policy to keep such details secret, "not least [for] the security of individuals".
Ms Petrova, who has known Ms Skripal since attending primary school with her in Russia, said relatives "don't want to talk", adding: "There aren't many of them left."
Ms Skripal's mother, uncle and elder brother have all died in recent years.
Life in UK
Ms Skripal, who was visiting her father from Moscow, has worked for multinationals, including Nike and PepsiCo, according to friends.
She moved to the UK with her father in 2010 when he was released as part of a spy swap, but returned to Moscow five years later.
She enjoyed her time in the UK, Ms Petrova said, adding that she passed her driving test and intended to apply for citizenship but later changed her mind.
"She told me she liked everything there," she said. "They had an amazing place, and amazing house."
She said Ms Skripal, who went to university in Moscow, returned to the city to live with her long-term boyfriend.
Ms Skripal had an "excellent" relationship with her father, she said, and had been the "perfect kid" who received excellent grades at school.
Ms Petrova said Ms Skripal "never shared her problems" – even when her father was arrested for spying in 2004, with the incident broadcast on Russian state TV.
She said "everyone was shocked" at the news, adding that Ms Skripal was a "normal kind of person".
Ms Petrova said no one knew who her father was before the arrest, but noted that Mr Skripal was often abroad and that his work had brought the family to Malta for a time.
She said Ms Skripal rarely spoke about her problems, but was "always smiling, just like her mother".
At the scene
BBC home affairs correspondent Dominic Casciani, in Salisbury

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It's been a busy Saturday morning for shoppers.
What many people have been worried about is whether the city will suffer in the long-term because of its new, and unfortunate, link to an extraordinary attempted murder.
City officials have already been talking to the businesses most affected by the security operation – including those still behind a police cordon at The Maltings precinct.
They're hoping to give them some marketing support and other advice so they can get back on their feet once they reopen.
As for the investigation, there has been virtually no discernible activity.
Police were again seen this morning at the graveyard on the London Road – but nobody appears to have seen the military units which were meant to be arriving to help the police.
Police activity has resumed at the cemetery where her brother, Alexander Skripal, and mother, Liudmila Skripal are buried.
Salisbury's London Road cemetery was cordoned off on Friday, but police confirmed officers were not exhuming a body.
Alexander Skripal died aged 43 last July in St Petersburg from liver failure, and her mother died of cancer in 2012.

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